v3.8.0

- print out Node.js and OS information

README.md

@@ -87,6 +87,7 @@ a double dash to prevent input files being used as option arguments:
                                 `wrap_iife`  Wrap IIFEs in parenthesis. Note: you may
                                              want to disable `negate_iife` under
                                              compressor options.
+    -O, --output-opts [options] Specify output options (`beautify` disabled by default).
     -o, --output <file>         Output file path (default STDOUT). Specify `ast` or
                                 `spidermonkey` to write UglifyJS or SpiderMonkey AST
                                 as JSON to STDOUT respectively.
@@ -735,6 +736,8 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
   annotation `/*@__PURE__*/` or `/*#__PURE__*/` immediately precedes the call. For
   example: `/*@__PURE__*/foo();`
 
+- `strings` (default: `true`) -- compact string concatenations.
+
 - `switches` (default: `true`) -- de-duplicate and remove unreachable `switch` branches
 
 - `toplevel` (default: `false`) -- drop unreferenced functions (`"funcs"`) and/or
@@ -845,8 +848,14 @@ can pass additional arguments that control the code output:
   statement.
 
 - `comments` (default `false`) -- pass `true` or `"all"` to preserve all
-  comments, `"some"` to preserve some comments, a regular expression string
+  comments, `"some"` to preserve multi-line comments that contain `@cc_on`,
-  (e.g. `/^!/`) or a function.
+  `@license`, or `@preserve` (case-insensitive), a regular expression string
+  (e.g. `/^!/`), or a function which returns `boolean`, e.g.
+  ```js
+  function(node, comment) {
+      return comment.value.indexOf("@type " + node.TYPE) >= 0;
+  }
+  ```
 
 - `indent_level` (default `4`)
 

bin/uglifyjs

@@ -36,6 +36,7 @@ program.option("-c, --compress [options]", "Enable compressor/specify compressor
 program.option("-m, --mangle [options]", "Mangle names/specify mangler options.", parse_js());
 program.option("--mangle-props [options]", "Mangle properties/specify mangler options.", parse_js());
 program.option("-b, --beautify [options]", "Beautify output/specify output options.", parse_js());
+program.option("-O, --output-opts [options]", "Output options (beautify disabled).", parse_js());
 program.option("-o, --output <file>", "Output file (default STDOUT).");
 program.option("--comments [filter]", "Preserve copyright comments in the output.");
 program.option("--config-file <file>", "Read minify() options from JSON file.");
@@ -53,13 +54,14 @@ program.option("--toplevel", "Compress and/or mangle variables in toplevel scope
 program.option("--verbose", "Print diagnostic messages.");
 program.option("--warn", "Print warning messages.");
 program.option("--wrap <name>", "Embed everything as a function with “exports” corresponding to “name” globally.");
+program.option("--reduce-test", "Reduce a standalone `console.log` based test case.");
 program.arguments("[files...]").parseArgv(process.argv);
 if (program.configFile) {
     options = JSON.parse(read_file(program.configFile));
     if (options.mangle && options.mangle.properties && options.mangle.properties.regex) {
         options.mangle.properties.regex = UglifyJS.parse(options.mangle.properties.regex, {
             expression: true
-        }).getValue();
+        }).value;
     }
 }
 if (!program.output && program.sourceMap && program.sourceMap.url != "inline") {
@@ -93,6 +95,10 @@ if (program.beautify) {
         options.output.beautify = true;
     }
 }
+if (program.outputOpts) {
+    if (program.beautify) fatal("--beautify cannot be used with --output-opts");
+    options.output = typeof program.outputOpts == "object" ? program.outputOpts : {};
+}
 if (program.comments) {
     if (typeof options.output != "object") options.output = {};
     options.output.comments = typeof program.comments == "string" ? program.comments : "some";
@@ -210,7 +216,15 @@ function run() {
     } catch (ex) {
         fatal(ex);
     }
-    var result = UglifyJS.minify(files, options);
+    if (program.reduceTest) {
+        // load on demand - assumes dev tree checked out
+        var reduce_test = require("../test/reduce");
+        var testcase = files[0] || files[Object.keys(files)[0]];
+        var result = reduce_test(testcase, options, {verbose: true});
+    }
+    else {
+        var result = UglifyJS.minify(files, options);
+    }
     if (result.error) {
         var ex = result.error;
         if (ex.name == "SyntaxError") {
@@ -370,7 +384,7 @@ function parse_js(flag) {
                 if (!(node instanceof UglifyJS.AST_Sequence)) throw node;
 
                 function to_string(value) {
-                    return value instanceof UglifyJS.AST_Constant ? value.getValue() : value.print_to_string({
+                    return value instanceof UglifyJS.AST_Constant ? value.value : value.print_to_string({
                         quote_keys: true
                     });
                 }

lib/ast.js

@@ -169,10 +169,7 @@ var AST_SimpleStatement = DEFNODE("SimpleStatement", "body", {
 }, AST_Statement);
 
 function walk_body(node, visitor) {
-    var body = node.body;
+    node.body.forEach(function(node) {
-    if (body instanceof AST_Statement) {
-        body._walk(visitor);
-    } else body.forEach(function(node) {
         node._walk(visitor);
     });
 }
@@ -351,7 +348,7 @@ var AST_Toplevel = DEFNODE("Toplevel", "globals", {
             filename: "wrap=" + JSON.stringify(name)
         }).transform(new TreeTransformer(function(node) {
             if (node instanceof AST_Directive && node.value == "$ORIG") {
-                return MAP.splice(body);
+                return List.splice(body);
             }
         }));
     },
@@ -370,7 +367,7 @@ var AST_Toplevel = DEFNODE("Toplevel", "globals", {
             filename: "enclose=" + JSON.stringify(args_values)
         }).transform(new TreeTransformer(function(node) {
             if (node instanceof AST_Directive && node.value == "$ORIG") {
-                return MAP.splice(body);
+                return List.splice(body);
             }
         }));
     }
@@ -618,7 +615,7 @@ var AST_PropAccess = DEFNODE("PropAccess", "expression property", {
     getProperty: function() {
         var p = this.property;
         if (p instanceof AST_Constant) {
-            return p.getValue();
+            return p.value;
         }
         if (p instanceof AST_UnaryPrefix
             && p.operator == "void"
@@ -824,9 +821,6 @@ var AST_This = DEFNODE("This", null, {
 
 var AST_Constant = DEFNODE("Constant", null, {
     $documentation: "Base class for all constants",
-    getValue: function() {
-        return this.value;
-    }
 });
 
 var AST_String = DEFNODE("String", "value quote", {
@@ -967,11 +961,13 @@ TreeWalker.prototype = {
     in_boolean_context: function() {
         var self = this.self();
         for (var i = 0, p; p = this.parent(i); i++) {
-            if (p instanceof AST_SimpleStatement
+            if (p instanceof AST_Conditional && p.condition === self
-                || p instanceof AST_Conditional && p.condition === self
                 || p instanceof AST_DWLoop && p.condition === self
                 || p instanceof AST_For && p.condition === self
                 || p instanceof AST_If && p.condition === self
+                || p instanceof AST_Return && p.in_bool
+                || p instanceof AST_Sequence && p.tail_node() !== self
+                || p instanceof AST_SimpleStatement
                 || p instanceof AST_UnaryPrefix && p.operator == "!" && p.expression === self) {
                 return true;
             }

lib/output.js

@@ -43,8 +43,6 @@
 
 "use strict";
 
-var EXPECT_DIRECTIVE = /^$|[;{][\s\n]*$/;
-
 function is_some_comments(comment) {
     // multiline comment
     return comment.type == "comment2" && /@preserve|@license|@cc_on/i.test(comment.value);
@@ -121,15 +119,20 @@ function OutputStream(options) {
         });
     } : function(str) {
         var s = "";
-        for (var i = 0; i < str.length; i++) {
+        for (var i = 0, j = 0; i < str.length; i++) {
-            if (is_surrogate_pair_head(str[i]) && !is_surrogate_pair_tail(str[i + 1])
+            var code = str.charCodeAt(i);
-                || is_surrogate_pair_tail(str[i]) && !is_surrogate_pair_head(str[i - 1])) {
+            if (is_surrogate_pair_head(code)) {
-                s += "\\u" + str.charCodeAt(i).toString(16);
+                if (is_surrogate_pair_tail(str.charCodeAt(i + 1))) {
-            } else {
+                    i++;
-                s += str[i];
+                    continue;
+                }
+            } else if (!is_surrogate_pair_tail(code)) {
+                continue;
             }
+            s += str.slice(j, i) + "\\u" + code.toString(16);
+            j = i + 1;
         }
-        return s;
+        return j == 0 ? str : s + str.slice(j);
     };
 
     function make_string(str, quote) {
@@ -378,7 +381,7 @@ function OutputStream(options) {
     };
 
     function force_semicolon() {
-        might_need_semicolon = false;
+        if (might_need_semicolon) print(";");
         print(";");
     }
 
@@ -585,17 +588,7 @@ function OutputStream(options) {
         force_semicolon : force_semicolon,
         to_utf8         : to_utf8,
         print_name      : function(name) { print(make_name(name)) },
-        print_string    : function(str, quote, escape_directive) {
+        print_string    : function(str, quote) { print(encode_string(str, quote)) },
-            var encoded = encode_string(str, quote);
-            if (escape_directive === true && encoded.indexOf("\\") === -1) {
-                // Insert semicolons to break directive prologue
-                if (!EXPECT_DIRECTIVE.test(OUTPUT)) {
-                    force_semicolon();
-                }
-                force_semicolon();
-            }
-            print(encoded);
-        },
         next_indent     : next_indent,
         with_indent     : with_indent,
         with_block      : with_block,
@@ -633,17 +626,10 @@ function OutputStream(options) {
         nodetype.DEFMETHOD("_codegen", generator);
     }
 
-    var in_directive = false;
+    var use_asm = false;
-    var active_scope = null;
-    var use_asm = null;
 
     AST_Node.DEFMETHOD("print", function(stream, force_parens) {
         var self = this, generator = self._codegen;
-        if (self instanceof AST_Scope) {
-            active_scope = self;
-        } else if (!use_asm && self instanceof AST_Directive && self.value == "use asm") {
-            use_asm = active_scope;
-        }
         function doit() {
             stream.prepend_comments(self);
             self.add_source_map(stream);
@@ -657,9 +643,6 @@ function OutputStream(options) {
             doit();
         }
         stream.pop_node();
-        if (self === use_asm) {
-            use_asm = null;
-        }
     });
     AST_Node.DEFMETHOD("_print", AST_Node.prototype.print);
 
@@ -799,7 +782,9 @@ function OutputStream(options) {
     PARENS(AST_Number, function(output) {
         var p = output.parent();
         if (p instanceof AST_PropAccess && p.expression === this) {
-            var value = this.getValue();
+            var value = this.value;
+            // https://github.com/mishoo/UglifyJS2/issues/115
+            // https://github.com/mishoo/UglifyJS2/pull/1009
             if (value < 0 || /^0/.test(make_num(value))) {
                 return true;
             }
@@ -828,7 +813,18 @@ function OutputStream(options) {
     /* -----[ PRINTERS ]----- */
 
     DEFPRINT(AST_Directive, function(self, output) {
-        output.print_string(self.value, self.quote);
+        var quote = self.quote;
+        var value = self.value;
+        switch (output.option("quote_style")) {
+          case 0:
+          case 2:
+            if (value.indexOf('"') == -1) quote = '"';
+            break;
+          case 1:
+            if (value.indexOf("'") == -1) quote = "'";
+            break;
+        }
+        output.print(quote + value + quote);
         output.semicolon();
     });
     DEFPRINT(AST_Debugger, function(self, output) {
@@ -840,30 +836,27 @@ function OutputStream(options) {
 
     function display_body(body, is_toplevel, output, allow_directives) {
         var last = body.length - 1;
-        in_directive = allow_directives;
+        var in_directive = allow_directives;
+        var was_asm = use_asm;
         body.forEach(function(stmt, i) {
-            if (in_directive === true && !(stmt instanceof AST_Directive ||
+            if (in_directive) {
-                stmt instanceof AST_EmptyStatement ||
+                if (stmt instanceof AST_Directive) {
-                (stmt instanceof AST_SimpleStatement && stmt.body instanceof AST_String)
+                    if (stmt.value == "use asm") use_asm = true;
-            )) {
+                } else if (!(stmt instanceof AST_EmptyStatement)) {
-                in_directive = false;
+                    if (stmt instanceof AST_SimpleStatement && stmt.body instanceof AST_String) {
-            }
+                        output.force_semicolon();
-            if (!(stmt instanceof AST_EmptyStatement)) {
+                    }
-                output.indent();
+                    in_directive = false;
-                stmt.print(output);
-                if (!(i == last && is_toplevel)) {
-                    output.newline();
-                    if (is_toplevel) output.newline();
                 }
             }
-            if (in_directive === true &&
+            if (stmt instanceof AST_EmptyStatement) return;
-                stmt instanceof AST_SimpleStatement &&
+            output.indent();
-                stmt.body instanceof AST_String
+            stmt.print(output);
-            ) {
+            if (i == last && is_toplevel) return;
-                in_directive = false;
+            output.newline();
-            }
+            if (is_toplevel) output.newline();
         });
-        in_directive = false;
+        use_asm = was_asm;
     }
 
     AST_StatementWithBody.DEFMETHOD("_do_print_body", function(output) {
@@ -1221,7 +1214,7 @@ function OutputStream(options) {
             output.print_string(prop);
             output.print("]");
         } else {
-            if (expr instanceof AST_Number && expr.getValue() >= 0) {
+            if (expr instanceof AST_Number && expr.value >= 0) {
                 if (!/[xa-f.)]/i.test(output.last())) {
                     output.print(".");
                 }
@@ -1345,27 +1338,34 @@ function OutputStream(options) {
         output.print("this");
     });
     DEFPRINT(AST_Constant, function(self, output) {
-        output.print(self.getValue());
+        output.print(self.value);
     });
     DEFPRINT(AST_String, function(self, output) {
-        output.print_string(self.getValue(), self.quote, in_directive);
+        output.print_string(self.value, self.quote);
     });
     DEFPRINT(AST_Number, function(self, output) {
         if (use_asm && self.start && self.start.raw != null) {
             output.print(self.start.raw);
         } else {
-            output.print(make_num(self.getValue()));
+            output.print(make_num(self.value));
         }
     });
 
     DEFPRINT(AST_RegExp, function(self, output) {
-        var regexp = self.getValue();
+        var regexp = self.value;
         var str = regexp.toString();
+        var end = str.lastIndexOf("/");
         if (regexp.raw_source) {
-            str = "/" + regexp.raw_source + str.slice(str.lastIndexOf("/"));
+            str = "/" + regexp.raw_source + str.slice(end);
+        } else if (end == 1) {
+            str = "/(?:)" + str.slice(end);
+        } else if (str.indexOf("/", 1) < end) {
+            str = "/" + str.slice(1, end).replace(/\\\\|[^/]?\//g, function(match) {
+                return match[0] == "\\" ? match : match.slice(0, -1) + "\\/";
+            }) + str.slice(end);
         }
-        output.print(output.to_utf8(str).replace(/\\(?:\0(?![0-9])|[^\0])/g, function(seq) {
+        output.print(output.to_utf8(str).replace(/\\(?:\0(?![0-9])|[^\0])/g, function(match) {
-            switch (seq[1]) {
+            switch (match[1]) {
               case "\n": return "\\n";
               case "\r": return "\\r";
               case "\t": return "\t";
@@ -1375,7 +1375,7 @@ function OutputStream(options) {
               case "\x0B": return "\v";
               case "\u2028": return "\\u2028";
               case "\u2029": return "\\u2029";
-              default: return seq;
+              default: return match;
             }
         }).replace(/[\n\r\u2028\u2029]/g, function(c) {
             switch (c) {

lib/parse.js

@@ -133,14 +133,10 @@ function is_letter(code) {
 }
 
 function is_surrogate_pair_head(code) {
-    if (typeof code == "string")
-        code = code.charCodeAt(0);
     return code >= 0xd800 && code <= 0xdbff;
 }
 
 function is_surrogate_pair_tail(code) {
-    if (typeof code == "string")
-        code = code.charCodeAt(0);
     return code >= 0xdc00 && code <= 0xdfff;
 }
 
@@ -790,9 +786,10 @@ function parse($TEXT, options) {
             var dir = S.in_directives;
             var body = expression(true);
             if (dir) {
-                var token = body.start;
+                if (body instanceof AST_String) {
-                if (body instanceof AST_String && token.raw.indexOf("\\") == -1) {
+                    var value = body.start.raw.slice(1, -1);
-                    S.input.add_directive(token.value);
+                    S.input.add_directive(value);
+                    body.value = value;
                 } else {
                     S.in_directives = dir = false;
                 }

lib/scope.js

@@ -428,6 +428,11 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options) {
             if (options.cache && node instanceof AST_Toplevel) {
                 node.globals.each(mangle);
             }
+            if (node instanceof AST_Defun && tw.has_directive("use asm")) {
+                var sym = new AST_SymbolRef(node.name);
+                sym.scope = node;
+                sym.reference(options);
+            }
             node.variables.each(function(def) {
                 if (!defer_redef(def)) mangle(def);
             });

lib/transform.js

@@ -52,7 +52,7 @@ TreeTransformer.prototype = new TreeWalker;
 
 (function(DEF) {
     function do_list(list, tw) {
-        return MAP(list, function(node) {
+        return List(list, function(node) {
             return node.transform(tw, true);
         });
     }

lib/utils.js

@@ -113,8 +113,8 @@ function return_true() { return true; }
 function return_this() { return this; }
 function return_null() { return null; }
 
-var MAP = (function() {
+var List = (function() {
-    function MAP(a, f, backwards) {
+    function List(a, f, backwards) {
         var ret = [], top = [], i;
         function doit() {
             var val = f(a[i], i);
@@ -149,14 +149,14 @@ var MAP = (function() {
         }
         return top.concat(ret);
     }
-    MAP.at_top = function(val) { return new AtTop(val) };
+    List.at_top = function(val) { return new AtTop(val); };
-    MAP.splice = function(val) { return new Splice(val) };
+    List.splice = function(val) { return new Splice(val); };
-    MAP.last = function(val) { return new Last(val) };
+    List.last = function(val) { return new Last(val); };
-    var skip = MAP.skip = {};
+    var skip = List.skip = {};
-    function AtTop(val) { this.v = val }
+    function AtTop(val) { this.v = val; }
-    function Splice(val) { this.v = val }
+    function Splice(val) { this.v = val; }
-    function Last(val) { this.v = val }
+    function Last(val) { this.v = val; }
-    return MAP;
+    return List;
 })();
 
 function push_uniq(array, el) {

package.json

@@ -3,7 +3,7 @@
   "description": "JavaScript parser, mangler/compressor and beautifier toolkit",
   "author": "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)",
   "license": "BSD-2-Clause",
-  "version": "3.7.2",
+  "version": "3.8.0",
   "engines": {
     "node": ">=0.8.0"
   },

test/compress/arrays.js

@@ -16,6 +16,7 @@ holes_and_undefined: {
 constant_join: {
     options = {
         evaluate: true,
+        strings: true,
         unsafe: true,
     }
     input: {
@@ -65,6 +66,7 @@ constant_join: {
 constant_join_2: {
     options = {
         evaluate: true,
+        strings: true,
         unsafe: true,
     }
     input: {
@@ -94,9 +96,11 @@ constant_join_2: {
 constant_join_3: {
     options = {
         evaluate: true,
+        strings: true,
         unsafe: true,
     }
     input: {
+        var foo, bar, baz;
         var a = [ null ].join();
         var b = [ , ].join();
         var c = [ , 1, , 3 ].join();
@@ -111,6 +115,7 @@ constant_join_3: {
         var l = [ foo, bar + "baz" ].join("");
     }
     expect: {
+        var foo, bar, baz;
         var a = "";
         var b = "";
         var c = ",1,,3";

test/compress/asm.js

@@ -166,3 +166,69 @@ asm_nested_functions: {
     }
     expect_exact: '0;function a(){"use asm";0.0}0;function b(){0;function c(){"use asm";0.0}0;function d(){0}0}0;'
 }
+
+issue_3636_1: {
+    mangle = {}
+    input: {
+        function n(stdlib, foreign, buffer) {
+            "use asm";
+            function add(x, y) {
+                x = x | 0;
+                y = y | 0;
+                return x + y | 0;
+            }
+            return {
+                add: add
+            };
+        }
+        console.log(new n().add("foo", 42));
+    }
+    expect: {
+        function n(o, e, u) {
+            "use asm";
+            function d(n, o) {
+                n = n | 0;
+                o = o | 0;
+                return n + o | 0;
+            }
+            return {
+                add: d
+            };
+        }
+        console.log(new n().add("foo", 42));
+    }
+    expect_stdout: "42"
+}
+
+issue_3636_2: {
+    mangle = {}
+    input: {
+        var n = function(stdlib, foreign, buffer) {
+            "use asm";
+            function add(x, y) {
+                x = x | 0;
+                y = y | 0;
+                return x + y | 0;
+            }
+            return {
+                add: add
+            };
+        };
+        console.log(new n().add("foo", 42));
+    }
+    expect: {
+        var n = function(n, o, e) {
+            "use asm";
+            function r(n, o) {
+                n = n | 0;
+                o = o | 0;
+                return n + o | 0;
+            }
+            return {
+                add: r
+            };
+        };
+        console.log(new n().add("foo", 42));
+    }
+    expect_stdout: "42"
+}

test/compress/booleans.js

@@ -86,3 +86,70 @@ issue_3465_3: {
     }
     expect_stdout: "PASS"
 }
+
+issue_2737_2: {
+    options = {
+        booleans: true,
+        inline: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function(bar) {
+            for (;bar();) break;
+        })(function qux() {
+            return console.log("PASS"), qux;
+        });
+    }
+    expect: {
+        (function(bar) {
+            for (;bar();) break;
+        })(function() {
+            return console.log("PASS"), 1;
+        });
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3658: {
+    options = {
+        booleans: true,
+        evaluate: true,
+        reduce_vars: true,
+    }
+    input: {
+        console.log(function f() {
+            console || f();
+            return "PASS";
+        }());
+    }
+    expect: {
+        console.log(function f() {
+            console || f();
+            return "PASS";
+        }());
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3690: {
+    options = {
+        booleans: true,
+        unused: true,
+    }
+    input: {
+        console.log(function(a) {
+            return function() {
+                return a = [ this ];
+            }() ? "PASS" : "FAIL";
+        }());
+    }
+    expect: {
+        console.log(function(a) {
+            return function() {
+                return 1;
+            }() ? "PASS" : "FAIL";
+        }());
+    }
+    expect_stdout: "PASS"
+}

test/compress/collapse_vars.js

@@ -5863,8 +5863,8 @@ issue_2974: {
         var c = 0;
         (function(b) {
             var a = 2;
-            for (; b.null = -4, c++, b.null && --a > 0;);
+            for (;c++, (!0).null && --a > 0;);
-        })(!0),
+        })(),
         console.log(c);
     }
     expect_stdout: "1"
@@ -7399,3 +7399,369 @@ issue_3628_2: {
     }
     expect_stdout: "foo bar"
 }
+
+issue_3641: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var a, b;
+        try {
+            a = "foo";
+            b = (a += (A.p = 0, "bar")) % 0;
+        } catch (e) {}
+        console.log(a, b);
+    }
+    expect: {
+        var a, b;
+        try {
+            a = "foo";
+            b = (a += (A.p = 0, "bar")) % 0;
+        } catch (e) {}
+        console.log(a, b);
+    }
+    expect_stdout: "foo undefined"
+}
+
+issue_3651: {
+    options = {
+        collapse_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a, b = "PASS";
+        try {
+            a = function() {
+                try {
+                    var c = 1;
+                    while (0 < --c);
+                } catch (e) {} finally {
+                    throw 42;
+                }
+            }();
+            b = "FAIL";
+            a.p;
+        } catch (e) {
+            console.log(b);
+        }
+    }
+    expect: {
+        var a, b = "PASS";
+        try {
+            a = function() {
+                try {
+                    var c = 1;
+                    while (0 < --c);
+                } catch (e) {} finally {
+                    throw 42;
+                }
+            }();
+            b = "FAIL";
+            a.p;
+        } catch (e) {
+            console.log(b);
+        }
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3671: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var a = 0;
+        try {
+            a++;
+            A += 0;
+            a = 1 + a;
+        } catch (e) {
+            console.log(a);
+        }
+    }
+    expect: {
+        var a = 0;
+        try {
+            a++;
+            A += 0;
+            a = 1 + a;
+        } catch (e) {
+            console.log(a);
+        }
+    }
+    expect_stdout: "1"
+}
+
+call_1: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        (function(a) {
+            a = console;
+            (function() {})();
+            a.log("PASS");
+        })();
+    }
+    expect: {
+        (function(a) {
+            (function() {})();
+            (a = console).log("PASS");
+        })();
+    }
+    expect_stdout: "PASS"
+}
+
+call_1_symbol: {
+    options = {
+        collapse_vars: true,
+        reduce_vars: true,
+    }
+    input: {
+        (function(a) {
+            function f() {}
+            a = console;
+            f();
+            a.log(typeof f);
+        })();
+    }
+    expect: {
+        (function(a) {
+            function f() {}
+            f();
+            (a = console).log(typeof f);
+        })();
+    }
+    expect_stdout: "function"
+}
+
+call_2: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        (function(a) {
+            a = console;
+            (function() {
+                return 42;
+                console.log("FAIL");
+            })();
+            a.log("PASS");
+        })();
+    }
+    expect: {
+        (function(a) {
+            (function() {
+                return 42;
+                console.log("FAIL");
+            })();
+            (a = console).log("PASS");
+        })();
+    }
+    expect_stdout: "PASS"
+}
+
+call_2_symbol: {
+    options = {
+        collapse_vars: true,
+        reduce_vars: true,
+    }
+    input: {
+        (function(a) {
+            function f() {
+                return 42;
+                console.log("FAIL");
+            }
+            a = console;
+            f();
+            a.log(typeof f);
+        })();
+    }
+    expect: {
+        (function(a) {
+            function f() {
+                return 42;
+                console.log("FAIL");
+            }
+            f();
+            (a = console).log(typeof f);
+        })();
+    }
+    expect_stdout: "function"
+}
+
+call_3: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        (function(a) {
+            a = console;
+            (function() {
+                a = {
+                    log: function() {
+                        console.log("PASS");
+                    }
+                }
+            })();
+            a.log("FAIL");
+        })();
+    }
+    expect: {
+        (function(a) {
+            a = console;
+            (function() {
+                a = {
+                    log: function() {
+                        console.log("PASS");
+                    }
+                }
+            })();
+            a.log("FAIL");
+        })();
+    }
+    expect_stdout: "PASS"
+}
+
+call_3_symbol: {
+    options = {
+        collapse_vars: true,
+        reduce_vars: true,
+    }
+    input: {
+        (function(a) {
+            function f() {
+                a = {
+                    log: function() {
+                        console.log(typeof f);
+                    }
+                }
+            }
+            a = console;
+            f();
+            a.log("FAIL");
+        })();
+    }
+    expect: {
+        (function(a) {
+            function f() {
+                a = {
+                    log: function() {
+                        console.log(typeof f);
+                    }
+                }
+            }
+            a = console;
+            f();
+            a.log("FAIL");
+        })();
+    }
+    expect_stdout: "function"
+}
+
+issue_3698_1: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var log = console.log;
+        var a, b = 0, c = 0;
+        (function() {
+            a = b;
+        })(b++, (b++, c++));
+        log(a, b, c);
+    }
+    expect: {
+        var log = console.log;
+        var a, b = 0, c = 0;
+        (function() {
+            a = b;
+        })(b++, (b++, c++));
+        log(a, b, c);
+    }
+    expect_stdout: "2 2 1"
+}
+
+issue_3698_2: {
+    options = {
+        collapse_vars: true,
+        reduce_vars: true,
+    }
+    input: {
+        var log = console.log;
+        var a, b = 0, c = 0, d = 1;
+        (function f() {
+            a = b;
+            d-- && f();
+        })(b++, (b++, c++));
+        log(a, b, c, d);
+    }
+    expect: {
+        var log = console.log;
+        var a, b = 0, c = 0, d = 1;
+        (function f() {
+            a = b;
+            d-- && f();
+        })(b++, (b++, c++));
+        log(a, b, c, d);
+    }
+    expect_stdout: "2 2 1 -1"
+}
+
+issue_3698_3: {
+    options = {
+        collapse_vars: true,
+        reduce_vars: true,
+    }
+    input: {
+        var a = 0, b = 0;
+        (function f(c) {
+            {
+                b++;
+                var bar_1 = (b = 1 + b, c = 0);
+                a-- && f();
+            }
+        })();
+        console.log(b);
+    }
+    expect: {
+        var a = 0, b = 0;
+        (function f(c) {
+            var bar_1 = (b = 1 + ++b, c = 0);
+            a-- && f();
+        })();
+        console.log(b);
+    }
+    expect_stdout: "2"
+}
+
+issue_3700: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var a = "FAIL";
+        try {
+            a = "PASS";
+            (function() {
+                throw 0;
+            })();
+            a = 1 + a;
+        } catch (e) {
+        }
+        console.log(a);
+    }
+    expect: {
+        var a = "FAIL";
+        try {
+            a = "PASS";
+            (function() {
+                throw 0;
+            })();
+            a = 1 + a;
+        } catch (e) {
+        }
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}

test/compress/comparisons.js

@@ -33,10 +33,10 @@ unsafe_comps: {
     }
     expect: {
         var obj1, obj2;
-        obj2 <  obj1 ? g1() : f1();
+        (obj2 <  obj1 ? g1 : f1)();
-        obj1 <  obj2 ? f2() : g2();
+        (obj1 <  obj2 ? f2 : g2)();
-        obj1 <  obj2 ? g3() : f3();
+        (obj1 <  obj2 ? g3 : f3)();
-        obj2 <  obj1 ? f4() : g4();
+        (obj2 <  obj1 ? f4 : g4)();
     }
 }
 

test/compress/concat-strings.js

@@ -26,7 +26,9 @@ concat_1: {
 }
 
 concat_2: {
-    options = {}
+    options = {
+        strings: true,
+    }
     input: {
         console.log(
             1 + (2 + 3),
@@ -55,7 +57,9 @@ concat_2: {
 }
 
 concat_3: {
-    options = {}
+    options = {
+        strings: true,
+    }
     input: {
         console.log(
             1 + 2 + (3 + 4 + 5),
@@ -84,7 +88,9 @@ concat_3: {
 }
 
 concat_4: {
-    options = {}
+    options = {
+        strings: true,
+    }
     input: {
         console.log(
             1 + "2" + (3 + 4 + 5),
@@ -113,7 +119,9 @@ concat_4: {
 }
 
 concat_5: {
-    options = {}
+    options = {
+        strings: true,
+    }
     input: {
         console.log(
             "1" + 2 + (3 + 4 + 5),
@@ -142,7 +150,9 @@ concat_5: {
 }
 
 concat_6: {
-    options = {}
+    options = {
+        strings: true,
+    }
     input: {
         console.log(
             "1" + "2" + (3 + 4 + 5),
@@ -171,6 +181,9 @@ concat_6: {
 }
 
 concat_7: {
+    options = {
+        strings: true,
+    }
     input: {
         console.log(
             "" + 1,
@@ -197,6 +210,9 @@ concat_7: {
 }
 
 concat_8: {
+    options = {
+        strings: true,
+    }
     input: {
         console.log(
             1 + "",
@@ -221,3 +237,20 @@ concat_8: {
     }
     expect_stdout: true
 }
+
+issue_3689: {
+    options = {
+        strings: true,
+    }
+    input: {
+        console.log(function(a) {
+            return a + ("" + (a[0] = 0));
+        }([]));
+    }
+    expect: {
+        console.log(function(a) {
+            return a + ("" + (a[0] = 0));
+        }([]));
+    }
+    expect_stdout: "00"
+}

test/compress/conditionals.js

@@ -41,7 +41,7 @@ ifs_2: {
     }
     expect: {
         foo ? x() : bar ? y() : baz && z();
-        foo ? x() : bar ? y() : baz ? z() : t();
+        (foo ? x : bar ? y : baz ? z : t)();
     }
 }
 
@@ -289,11 +289,50 @@ cond_5: {
         }
     }
     expect: {
-        some_condition() && some_other_condition() ? do_something() : alternate();
+        (some_condition() && some_other_condition() ? do_something : alternate)();
         some_condition() && some_other_condition() && do_something();
     }
 }
 
+cond_6: {
+    options = {
+        booleans: true,
+        conditionals: true,
+    }
+    input: {
+        x ? a : b;
+        x ? a : a;
+
+        x ? y ? a : b : c;
+        x ? y ? a : a : b;
+        x ? y ? a : b : b;
+        x ? y ? a : b : a;
+        x ? y ? a : a : a;
+
+        x ? a : y ? b : c;
+        x ? a : y ? a : b;
+        x ? a : y ? b : b;
+        x ? a : y ? b : a;
+        x ? a : y ? a : a;
+    }
+    expect: {
+        x ? a : b;
+        x, a;
+
+        x ? y ? a : b : c;
+        x ? (y, a) : b;
+        x && y ? a : b;
+        !x || y ? a : b;
+        x && y, a;
+
+        x ? a : y ? b : c;
+        x || y ? a : b;
+        x ? a : (y, b);
+        !x && y ? b : a;
+        !x && y, a;
+    }
+}
+
 cond_7: {
     options = {
         conditionals: true,
@@ -663,6 +702,87 @@ cond_9: {
     }
 }
 
+cond_10: {
+    options = {
+        conditionals: true,
+        if_return: true,
+    }
+    input: {
+        function f(a) {
+            if (1 == a) return "foo";
+            if (2 == a) return "foo";
+            if (3 == a) return "foo";
+            if (4 == a) return 42;
+            if (5 == a) return "foo";
+            if (6 == a) return "foo";
+            return "bar";
+        }
+        console.log(f(1), f(2), f(3), f(4), f(5), f(6), f(7));
+    }
+    expect: {
+        function f(a) {
+            return 1 == a || 2 == a || 3 == a ? "foo" : 4 == a ? 42 : 5 == a || 6 == a ? "foo" : "bar";
+        }
+        console.log(f(1), f(2), f(3), f(4), f(5), f(6), f(7));
+    }
+    expect_stdout: "foo foo foo 42 foo foo bar"
+}
+
+cond_11: {
+    options = {
+        conditionals: true,
+    }
+    input: {
+        var o = {
+            p: "foo",
+            q: function() {
+                return this.p;
+            }
+        };
+        function f() {
+            return "bar";
+        }
+        function g(a) {
+            return a ? f() : o.q();
+        }
+        console.log(g(0), g(1));
+    }
+    expect: {
+        var o = {
+            p: "foo",
+            q: function() {
+                return this.p;
+            }
+        };
+        function f() {
+            return "bar";
+        }
+        function g(a) {
+            return a ? f() : o.q();
+        }
+        console.log(g(0), g(1));
+    }
+    expect_stdout: "foo bar"
+}
+
+cond_12: {
+    options = {
+        conditionals: true,
+    }
+    input: {
+        x ? y && a : a;
+        x ? y || a : a;
+        x ? a : y && a;
+        x ? a : y || a;
+    }
+    expect: {
+        (!x || y) && a;
+        x && y || a;
+        (x || y) && a;
+        !x && y || a;
+    }
+}
+
 ternary_boolean_consequent: {
     options = {
         booleans: true,
@@ -1515,3 +1635,34 @@ issue_3576: {
     }
     expect_stdout: "PASS"
 }
+
+issue_3668: {
+    options = {
+        conditionals: true,
+        if_return: true,
+    }
+    input: {
+        function f() {
+            try {
+                var undefined = typeof f;
+                if (!f) return undefined;
+                return;
+            } catch (e) {
+                return "FAIL";
+            }
+        }
+        console.log(f());
+    }
+    expect: {
+        function f() {
+            try {
+                var undefined = typeof f;
+                return f ? void 0 : undefined;
+            } catch (e) {
+                return "FAIL";
+            }
+        }
+        console.log(f());
+    }
+    expect_stdout: "undefined"
+}

test/compress/dead-code.js

@@ -141,207 +141,6 @@ try_catch_finally: {
     ]
 }
 
-accessor: {
-    options = {
-        side_effects: true,
-    }
-    input: {
-        ({
-            get a() {},
-            set a(v){
-                this.b = 2;
-            },
-            b: 1
-        });
-    }
-    expect: {}
-}
-
-issue_2233_1: {
-    options = {
-        pure_getters: "strict",
-        side_effects: true,
-        unsafe: true,
-    }
-    input: {
-        Array.isArray;
-        Boolean;
-        console.log;
-        Date;
-        decodeURI;
-        decodeURIComponent;
-        encodeURI;
-        encodeURIComponent;
-        Error.name;
-        escape;
-        eval;
-        EvalError;
-        Function.length;
-        isFinite;
-        isNaN;
-        JSON;
-        Math.random;
-        Number.isNaN;
-        parseFloat;
-        parseInt;
-        RegExp;
-        Object.defineProperty;
-        String.fromCharCode;
-        RangeError;
-        ReferenceError;
-        SyntaxError;
-        TypeError;
-        unescape;
-        URIError;
-    }
-    expect: {}
-    expect_stdout: true
-}
-
-global_timeout_and_interval_symbols: {
-    options = {
-        pure_getters: "strict",
-        side_effects: true,
-        unsafe: true,
-    }
-    input: {
-        // These global symbols do not exist in the test sandbox
-        // and must be tested separately.
-        clearInterval;
-        clearTimeout;
-        setInterval;
-        setTimeout;
-    }
-    expect: {}
-}
-
-issue_2233_2: {
-    options = {
-        pure_getters: "strict",
-        reduce_funcs: true,
-        reduce_vars: true,
-        side_effects: true,
-        unsafe: true,
-        unused: true,
-    }
-    input: {
-        var RegExp;
-        Array.isArray;
-        RegExp;
-        UndeclaredGlobal;
-        function foo() {
-            var Number;
-            AnotherUndeclaredGlobal;
-            Math.sin;
-            Number.isNaN;
-        }
-    }
-    expect: {
-        var RegExp;
-        UndeclaredGlobal;
-        function foo() {
-            var Number;
-            AnotherUndeclaredGlobal;
-            Number.isNaN;
-        }
-    }
-}
-
-issue_2233_3: {
-    options = {
-        pure_getters: "strict",
-        reduce_funcs: true,
-        reduce_vars: true,
-        side_effects: true,
-        toplevel: true,
-        unsafe: true,
-        unused: true,
-    }
-    input: {
-        var RegExp;
-        Array.isArray;
-        RegExp;
-        UndeclaredGlobal;
-        function foo() {
-            var Number;
-            AnotherUndeclaredGlobal;
-            Math.sin;
-            Number.isNaN;
-        }
-    }
-    expect: {
-        UndeclaredGlobal;
-    }
-}
-
-global_fns: {
-    options = {
-        side_effects: true,
-        unsafe: true,
-    }
-    input: {
-        Boolean(1, 2);
-        decodeURI(1, 2);
-        decodeURIComponent(1, 2);
-        Date(1, 2);
-        encodeURI(1, 2);
-        encodeURIComponent(1, 2);
-        Error(1, 2);
-        escape(1, 2);
-        EvalError(1, 2);
-        isFinite(1, 2);
-        isNaN(1, 2);
-        Number(1, 2);
-        Object(1, 2);
-        parseFloat(1, 2);
-        parseInt(1, 2);
-        RangeError(1, 2);
-        ReferenceError(1, 2);
-        String(1, 2);
-        SyntaxError(1, 2);
-        TypeError(1, 2);
-        unescape(1, 2);
-        URIError(1, 2);
-        try {
-            Function(1, 2);
-        } catch (e) {
-            console.log(e.name);
-        }
-        try {
-            RegExp(1, 2);
-        } catch (e) {
-            console.log(e.name);
-        }
-        try {
-            Array(NaN);
-        } catch (e) {
-            console.log(e.name);
-        }
-    }
-    expect: {
-        try {
-            Function(1, 2);
-        } catch (e) {
-            console.log(e.name);
-        }
-        try {
-            RegExp(1, 2);
-        } catch (e) {
-            console.log(e.name);
-        }
-        try {
-            Array(NaN);
-        } catch (e) {
-            console.log(e.name);
-        }
-    }
-    expect_stdout: [
-        "SyntaxError",
-        "SyntaxError",
-        "RangeError",
-    ]
-}
-
 collapse_vars_assignment: {
     options = {
         collapse_vars: true,
@@ -863,23 +662,6 @@ issue_2749: {
     expect_stdout: "PASS"
 }
 
-unsafe_builtin: {
-    options = {
-        side_effects: true,
-        unsafe: true,
-    }
-    input: {
-        (!w).constructor(x);
-        Math.abs(y);
-        [ 1, 2, z ].valueOf();
-    }
-    expect: {
-        w, x;
-        y;
-        z;
-    }
-}
-
 issue_2860_1: {
     options = {
         dead_code: true,
@@ -941,24 +723,6 @@ issue_2929: {
     expect_stdout: "PASS"
 }
 
-unsafe_string_replace: {
-    options = {
-        side_effects: true,
-        unsafe: true,
-    }
-    input: {
-        "foo".replace("f", function() {
-            console.log("PASS");
-        });
-    }
-    expect: {
-        "foo".replace("f", function() {
-            console.log("PASS");
-        });
-    }
-    expect_stdout: "PASS"
-}
-
 issue_3402: {
     options = {
         dead_code: true,
@@ -1066,6 +830,7 @@ issue_3552: {
 unreachable_assign: {
     options = {
         dead_code: true,
+        strings: true,
     }
     input: {
         console.log(A = "P" + (A = "A" + (B = "S" + (A = B = "S"))), A, B);

test/compress/directives.js

@@ -93,3 +93,41 @@ issue_3166: {
         }
     }
 }
+
+valid_after_invalid_1: {
+    input: {
+        console.log(typeof function() {
+            "use\x20strict";
+            "use strict";
+            return this;
+        }());
+    }
+    expect: {
+        console.log(typeof function() {
+            "use\x20strict";
+            "use strict";
+            return this;
+        }());
+    }
+    expect_stdout: "undefined"
+}
+
+valid_after_invalid_2: {
+    options = {
+        directives: true,
+    }
+    input: {
+        console.log(typeof function() {
+            "use\x20strict";
+            "use strict";
+            return this;
+        }());
+    }
+    expect: {
+        console.log(typeof function() {
+            "use strict";
+            return this;
+        }());
+    }
+    expect_stdout: "undefined"
+}

test/compress/drop-unused.js

@@ -699,18 +699,6 @@ iife: {
     }
 }
 
-drop_value: {
-    options = {
-        side_effects: true,
-    }
-    input: {
-        (1, [2, foo()], 3, {a:1, b:bar()});
-    }
-    expect: {
-        foo(), bar();
-    }
-}
-
 issue_1539: {
     options = {
         collapse_vars: true,
@@ -1203,10 +1191,10 @@ issue_2105_1: {
     input: {
         !function(factory) {
             factory();
-        }( function() {
+        }(function() {
             return function(fn) {
                 fn()().prop();
-            }( function() {
+            }(function() {
                 function bar() {
                     var quux = function() {
                         console.log("PASS");
@@ -1217,7 +1205,7 @@ issue_2105_1: {
                     return { prop: foo };
                 }
                 return bar;
-            } );
+            });
         });
     }
     expect: {
@@ -1247,10 +1235,10 @@ issue_2105_2: {
     input: {
         !function(factory) {
             factory();
-        }( function() {
+        }(function() {
             return function(fn) {
                 fn()().prop();
-            }( function() {
+            }(function() {
                 function bar() {
                     var quux = function() {
                         console.log("PASS");
@@ -1261,7 +1249,7 @@ issue_2105_2: {
                     return { prop: foo };
                 }
                 return bar;
-            } );
+            });
         });
     }
     expect: {
@@ -1270,6 +1258,44 @@ issue_2105_2: {
     expect_stdout: "PASS"
 }
 
+issue_2105_3: {
+    options = {
+        inline: true,
+        passes: 2,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        !function(factory) {
+            factory();
+        }(function() {
+            return function(fn) {
+                fn()().prop();
+            }(function() {
+                function bar() {
+                    var quux = function() {
+                        console.log("PASS");
+                    }, foo = function() {
+                        console.log;
+                        quux();
+                    };
+                    return { prop: foo };
+                }
+                return bar;
+            });
+        });
+    }
+    expect: {
+        !void void {
+            prop: function() {
+                console.log;
+                void console.log("PASS");
+            }
+        }.prop();
+    }
+    expect_stdout: "PASS"
+}
+
 issue_2226_1: {
     options = {
         side_effects: true,
@@ -2266,3 +2292,124 @@ issue_3598: {
     }
     expect_stdout: "PASS"
 }
+
+self_assign: {
+    options = {
+        passes: 2,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        function d(a) {
+            a = a;
+        }
+        function e(a, b) {
+            a = b;
+            b = a;
+        }
+        function f(a, b, c) {
+            a = b;
+            b = c;
+            c = a;
+        }
+        function g(a, b, c) {
+            a = a * b + c;
+        }
+    }
+    expect: {
+        function d(a) {}
+        function e(a, b) {}
+        function f(a, b, c) {}
+        function g(a, b, c) {}
+    }
+}
+
+function_argument_reference: {
+    options = {
+        keep_fargs: false,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var a = 1, b = 42;
+        function f(a) {
+            b <<= a;
+        }
+        f();
+        console.log(a, b);
+    }
+    expect: {
+        var a = 1, b = 42;
+        function f(a) {
+            b <<= a;
+        }
+        f();
+        console.log(a, b);
+    }
+    expect_stdout: "1 42"
+}
+
+function_parameter_ie8: {
+    options = {
+        ie8: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function() {
+            var a;
+            function f() {
+                console.log("PASS");
+            }
+            f(a = 1 + a);
+        })();
+    }
+    expect: {
+        (function() {
+            (function f() {
+                console.log("PASS");
+            })();
+        })();
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3664: {
+    options = {
+        pure_getters: "strict",
+        unused: true,
+    }
+    input: {
+        console.log(function() {
+            var a, b = (a = (a = [ b && console.log("FAIL") ]).p = 0, 0);
+            return "PASS";
+        }());
+    }
+    expect: {
+        console.log(function() {
+            var b = ([ b && console.log("FAIL") ].p = 0, 0);
+            return "PASS";
+        }());
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3673: {
+    options = {
+        pure_getters: "strict",
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a;
+        (a = [ a ]).p = 42;
+        console.log("PASS");
+    }
+    expect: {
+        var a;
+        (a = [ a ]).p = 42;
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}

test/compress/functions.js

@@ -266,12 +266,7 @@ issue_2084: {
     }
     expect: {
         var c = 0;
-        !function() {
+        23..toString(),
-            var c;
-            c = 1 + (c = -1),
-            c = 1 + (c = 0),
-            0 !== 23..toString() && (c = 1 + c);
-        }(),
         console.log(c);
     }
     expect_stdout: "0"
@@ -1281,7 +1276,7 @@ issue_2630_3: {
         (function() {
             (function f1(a) {
                 f2();
-                --x >= 0 && f1({});
+                --x >= 0 && f1();
             })(a++);
             function f2() {
                 a++;
@@ -1911,14 +1906,14 @@ issue_2737_2: {
     }
     input: {
         (function(bar) {
-            for (;bar(); ) break;
+            for (;bar();) break;
         })(function qux() {
             return console.log("PASS"), qux;
         });
     }
     expect: {
         (function(bar) {
-            for (;bar(); ) break;
+            for (;bar();) break;
         })(function qux() {
             return console.log("PASS"), qux;
         });
@@ -2249,7 +2244,7 @@ issue_3076: {
         var c = "PASS";
         (function(b) {
             var n = 2;
-            while (--b + (e = void 0, e && (c = "FAIL"), e = 5, 1).toString() && --n > 0);
+            while (--b + (e = void 0, e && (c = "FAIL"), e = 5, 1..toString()) && --n > 0);
             var e;
         })(2),
         console.log(c);
@@ -3705,3 +3700,88 @@ pr_3595_4: {
     }
     expect_stdout: "PASS"
 }
+
+issue_3679_1: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        (function() {
+            var f = function() {};
+            f.g = function() {
+                console.log("PASS");
+            };
+            f.g();
+        })();
+    }
+    expect: {
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3679_2: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        passes: 2,
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        (function() {
+            "use strict";
+            var f = function() {};
+            f.g = function() {
+                console.log("PASS");
+            };
+            f.g();
+        })();
+    }
+    expect: {
+        (function() {
+            "use strict";
+            console.log("PASS");
+        })();
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3679_3: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        functions: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        (function() {
+            var f = function() {};
+            f.p = "PASS";
+            f.g = function() {
+                console.log(f.p);
+            };
+            f.g();
+        })();
+    }
+    expect: {
+        (function() {
+            function f() {};
+            f.p = "PASS";
+            (f.g = function() {
+                console.log(f.p);
+            })();
+        })();
+    }
+    expect_stdout: "PASS"
+}

test/compress/hoist_props.js

@@ -664,7 +664,7 @@ issue_2519: {
     }
     expect: {
         function testFunc() {
-            return 1 * ((6 + 5) / 2);
+            return +((6 + 5) / 2);
         }
         console.log(testFunc());
     }

test/compress/ie8.js

@@ -2361,3 +2361,40 @@ issue_3542: {
     }
     expect_stdout: "1"
 }
+
+issue_3703: {
+    options = {
+        ie8: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = "PASS";
+        function f() {
+            var b;
+            function g() {
+                a = "FAIL";
+            }
+            var c = g;
+            function h() {
+                f;
+            }
+            a ? b |= c : b.p;
+        }
+        f();
+        console.log(a);
+    }
+    expect: {
+        var a = "PASS";
+        (function() {
+            var b;
+            var c = function g() {
+                a = "FAIL";
+            };
+            a ? b |= c : b.p;
+        })();
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}

test/compress/issue-1034.js

@@ -30,7 +30,7 @@ non_hoisted_function_after_return: {
     }
     expect: {
         function foo(x) {
-            return x ? bar() : baz();
+            return (x ? bar : baz)();
             function bar() { return 7 }
             function baz() { return 8 }
         }
@@ -181,7 +181,7 @@ non_hoisted_function_after_return_strict: {
     expect: {
         "use strict";
         function foo(x) {
-            return x ? bar() : baz();
+            return (x ? bar : baz)();
             function bar() { return 7 }
             function baz() { return 8 }
         }

test/compress/issue-1770.js

@@ -46,7 +46,7 @@ mangle_props: {
             obj[1/0],
             obj["Infinity"],
             obj[-1/0],
-            obj[-1/0],
+            obj[-(1/0)],
             obj["-Infinity"],
             obj[null],
             obj["null"]

test/compress/issue-269.js

@@ -1,98 +1,111 @@
 issue_269_1: {
-	options = {
+    options = {
         unsafe: true,
     }
-	input: {
+    input: {
-		f(
+        var x = {};
-			String(x),
+        console.log(
-			Number(x),
+            String(x),
-			Boolean(x),
+            Number(x),
+            Boolean(x),
 
-			String(),
+            String(),
-			Number(),
+            Number(),
-			Boolean()
+            Boolean()
-		);
+        );
-	}
+    }
-	expect: {
+    expect: {
-		f(
+        var x = {};
-			x + '', +x, !!x,
+        console.log(
-			'', 0, false
+            x + "", +x, !!x,
-		);
+            "", 0, false
-	}
+        );
+    }
+    expect_stdout: true
 }
 
 issue_269_dangers: {
-	options = {
+    options = {
         unsafe: true,
     }
-	input: {
+    input: {
-		f(
+        var x = {};
-			String(x, x),
+        console.log(
-			Number(x, x),
+            String(x, x),
-			Boolean(x, x)
+            Number(x, x),
-		);
+            Boolean(x, x)
-	}
+        );
-	expect: {
+    }
-		f(String(x, x), Number(x, x), Boolean(x, x));
+    expect: {
-	}
+        var x = {};
+        console.log(String(x, x), Number(x, x), Boolean(x, x));
+    }
+    expect_stdout: true
 }
 
 issue_269_in_scope: {
-	options = {
+    options = {
         unsafe: true,
     }
-	input: {
+    input: {
-		var String, Number, Boolean;
+        var String, Number, Boolean;
-		f(
+        var x = {};
-			String(x),
+        console.log(
-			Number(x, x),
+            String(x),
-			Boolean(x)
+            Number(x, x),
-		);
+            Boolean(x)
-	}
+        );
-	expect: {
+    }
-		var String, Number, Boolean;
+    expect: {
-		f(String(x), Number(x, x), Boolean(x));
+        var String, Number, Boolean;
-	}
+        var x = {};
+        console.log(String(x), Number(x, x), Boolean(x));
+    }
+    expect_stdout: true
 }
 
 strings_concat: {
-	options = {
+    options = {
+        strings: true,
         unsafe: true,
     }
-	input: {
+    input: {
-		f(
+        var x = {};
-			String(x + 'str'),
+        console.log(
-			String('str' + x)
+            String(x + "str"),
-		);
+            String("str" + x)
-	}
+        );
-	expect: {
+    }
-		f(
+    expect: {
-			x + 'str',
+        var x = {};
-			'str' + x
+        console.log(
-		);
+            x + "str",
-	}
+            "str" + x
+        );
+    }
+    expect_stdout: true
 }
 
 regexp: {
-	options = {
+    options = {
         evaluate: true,
         unsafe: true,
     }
-	input: {
+    input: {
-		RegExp("foo");
+        RegExp("foo");
-		RegExp("bar", "ig");
+        RegExp("bar", "ig");
-		RegExp(foo);
+        RegExp(foo);
-		RegExp("bar", ig);
+        RegExp("bar", ig);
-		RegExp("should", "fail");
+        RegExp("should", "fail");
-	}
+    }
-	expect: {
+    expect: {
-		/foo/;
+        /foo/;
-		/bar/ig;
+        /bar/ig;
-		RegExp(foo);
+        RegExp(foo);
-		RegExp("bar", ig);
+        RegExp("bar", ig);
-		RegExp("should", "fail");
+        RegExp("should", "fail");
-	}
+    }
-	expect_warnings: [
+    expect_warnings: [
-		'WARN: Error converting RegExp("should","fail") [test/compress/issue-269.js:5,2]',
+        'WARN: Error converting RegExp("should","fail") [test/compress/issue-269.js:5,8]',
-	]
+    ]
 }

test/compress/issue-640.js

@@ -21,7 +21,7 @@ cond_5: {
         }
     }
     expect: {
-        some_condition() && some_other_condition() ? do_something() : alternate();
+        (some_condition() && some_other_condition() ? do_something : alternate)();
         if (some_condition() && some_other_condition()) do_something();
     }
 }

test/compress/keep_fargs.js

@@ -728,7 +728,7 @@ issue_2630_3: {
         (function() {
             (function f1() {
                 f2();
-                --x >= 0 && f1({});
+                --x >= 0 && f1();
             })(a++);
             function f2() {
                 a++;
@@ -1369,7 +1369,7 @@ recursive_iife_1: {
     }
     expect: {
         console.log(function f(a, b) {
-            return b || f("FAIL", "PASS");
+            return b || f(0, "PASS");
         }());
     }
     expect_stdout: "PASS"
@@ -1388,7 +1388,7 @@ recursive_iife_2: {
     }
     expect: {
         console.log(function f(a, b) {
-            return b || f("FAIL", "PASS");
+            return b || f(0, "PASS");
         }(0, 0));
     }
     expect_stdout: "PASS"
@@ -1416,7 +1416,7 @@ recursive_iife_3: {
         var a = 1, c = "PASS";
         (function() {
             (function f(b, d, e) {
-                a-- && f(null, 42, 0);
+                a-- && f(0, 42, 0);
                 e && (c = "FAIL");
                 d && d.p;
             })();

test/compress/loops.js

@@ -6,7 +6,7 @@ while_becomes_for: {
         while (foo()) bar();
     }
     expect: {
-        for (; foo(); ) bar();
+        for (;foo();) bar();
     }
 }
 
@@ -19,7 +19,7 @@ drop_if_break_1: {
             if (foo()) break;
     }
     expect: {
-        for (; !foo(););
+        for (;!foo(););
     }
 }
 
@@ -32,7 +32,7 @@ drop_if_break_2: {
             if (foo()) break;
     }
     expect: {
-        for (; bar() && !foo(););
+        for (;bar() && !foo(););
     }
 }
 
@@ -70,7 +70,7 @@ drop_if_break_4: {
         }
     }
     expect: {
-        for (; bar() && (x(), y(), !foo());) z(), k();
+        for (;bar() && (x(), y(), !foo());) z(), k();
     }
 }
 
@@ -82,7 +82,7 @@ drop_if_else_break_1: {
         for (;;) if (foo()) bar(); else break;
     }
     expect: {
-        for (; foo(); ) bar();
+        for (;foo();) bar();
     }
 }
 
@@ -97,7 +97,7 @@ drop_if_else_break_2: {
         }
     }
     expect: {
-        for (; bar() && foo();) baz();
+        for (;bar() && foo();) baz();
     }
 }
 
@@ -114,7 +114,7 @@ drop_if_else_break_3: {
         }
     }
     expect: {
-        for (; bar() && foo();) {
+        for (;bar() && foo();) {
             baz();
             stuff1();
             stuff2();
@@ -138,7 +138,7 @@ drop_if_else_break_4: {
         }
     }
     expect: {
-        for (; bar() && (x(), y(), foo());) baz(), z(), k();
+        for (;bar() && (x(), y(), foo());) baz(), z(), k();
     }
 }
 
@@ -523,13 +523,13 @@ issue_2740_1: {
         loops: true,
     }
     input: {
-        for (; ; ) break;
+        for (;;) break;
-        for (a(); ; ) break;
+        for (a();;) break;
-        for (; b(); ) break;
+        for (;b();) break;
-        for (c(); d(); ) break;
+        for (c(); d();) break;
-        for (; ; e()) break;
+        for (;;e()) break;
-        for (f(); ; g()) break;
+        for (f();; g()) break;
-        for (; h(); i()) break;
+        for (;h(); i()) break;
         for (j(); k(); l()) break;
     }
     expect: {
@@ -574,9 +574,11 @@ issue_2740_3: {
         console.log(x, y);
     }
     expect: {
-        L1: for (var x = 0; x < 3; x++)
+        L1: for (var x = 0; x < 3; x++) {
-            for (var y = 0; y < 2; y++)
+            var y = 0;
+            if (y < 2)
                 break L1;
+        }
         console.log(x, y);
     }
     expect_stdout: "0 0"
@@ -668,7 +670,7 @@ issue_3371: {
             function a() {
                 console.log("PASS");
             }
-            for (; a(); );
+            for (;a(););
         })();
     }
     expect_stdout: "PASS"
@@ -753,3 +755,175 @@ empty_for_in_side_effects: {
         "WARN: Side effects in object of for-in loop [test/compress/loops.js:1,17]",
     ]
 }
+
+issue_3631_1: {
+    options = {
+        dead_code: true,
+        evaluate: true,
+        loops: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var c = 0;
+        L: do {
+            for (;;) continue L;
+            var b = 1;
+        } while (b && c++);
+        console.log(c);
+    }
+    expect: {
+        var c = 0;
+        do {
+            var b;
+        } while (b && c++);
+        console.log(c);
+    }
+    expect_stdout: "0"
+}
+
+issue_3631_2: {
+    options = {
+        dead_code: true,
+        evaluate: true,
+        loops: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        L: for (var a = 1; a--; console.log(b)) {
+            for (;;) continue L;
+            var b = "FAIL";
+        }
+    }
+    expect: {
+        for (var a = 1; a--; console.log(b))
+            var b;
+    }
+    expect_stdout: "undefined"
+}
+
+loop_if_break: {
+    options = {
+        dead_code: true,
+        loops: true,
+    }
+    input: {
+        function f(a, b) {
+            try {
+                while (a) {
+                    if (b) {
+                        break;
+                        var c = 42;
+                        console.log(c);
+                    } else {
+                        var d = false;
+                        throw d;
+                    }
+                }
+            } catch (e) {
+                console.log("E:", e);
+            }
+            console.log(a, b, c, d);
+        }
+        f(0, 0);
+        f(0, 1);
+        f(1, 0);
+        f(1, 1);
+    }
+    expect: {
+        function f(a, b) {
+            try {
+                for (;a && !b;) {
+                    var d = false;
+                    throw d;
+                    var c;
+                }
+            } catch (e) {
+                console.log("E:", e);
+            }
+            console.log(a, b, c, d);
+        }
+        f(0, 0);
+        f(0, 1);
+        f(1, 0);
+        f(1, 1);
+    }
+    expect_stdout: [
+        "0 0 undefined undefined",
+        "0 1 undefined undefined",
+        "E: false",
+        "1 0 undefined false",
+        "1 1 undefined undefined",
+    ]
+}
+
+loop_return: {
+    options = {
+        dead_code: true,
+        loops: true,
+    }
+    input: {
+        function f(a) {
+            while (a) return 42;
+            return "foo";
+        }
+        console.log(f(0), f(1));
+    }
+    expect: {
+        function f(a) {
+            if (a) return 42;
+            return "foo";
+        }
+        console.log(f(0), f(1));
+    }
+    expect_stdout: "foo 42"
+}
+
+issue_3634_1: {
+    options = {
+        loops: true,
+    }
+    input: {
+        var b = 0;
+        L: while (++b < 2)
+            while (1)
+                if (b) break L;
+        console.log(b);
+    }
+    expect: {
+        var b = 0;
+        L: for (;++b < 2;)
+            for (;1;)
+                if (b) break L;
+        console.log(b);
+    }
+    expect_stdout: "1"
+}
+
+issue_3634_2: {
+    options = {
+        loops: true,
+    }
+    input: {
+        var b = 0;
+        L: while (++b < 2)
+            while (1)
+                if (!b)
+                    continue L;
+                else
+                    break L;
+        console.log(b);
+    }
+    expect: {
+        var b = 0;
+        L: for (;++b < 2;)
+            for (;1;)
+                if (!b)
+                    continue L;
+                else
+                    break L;
+        console.log(b);
+    }
+    expect_stdout: "1"
+}

test/compress/numbers.js

@@ -91,7 +91,7 @@ evaluate_1: {
     expect: {
         console.log(
             x + 1 + 2,
-            1 * x * 2,
+            2 * x,
             +x + 1 + 2,
             1 + x + 2 + 3,
             3 | x,
@@ -173,7 +173,7 @@ evaluate_2: {
         var x = "42", y = null;
         [
             x + 1 + 2,
-            1 * x * 2,
+            2 * x,
             +x + 1 + 2,
             1 + x + 2 + 3,
             3 | x,
@@ -669,6 +669,9 @@ issue_1710: {
 }
 
 unary_binary_parenthesis: {
+    options = {
+        evaluate: true,
+    }
     input: {
         var v = [ 0, 1, NaN, Infinity, null, undefined, true, false, "", "foo", /foo/ ];
         v.forEach(function(x) {
@@ -979,3 +982,272 @@ unsafe_math_swap_constant: {
     }
     expect_stdout: "6 6 7 6 6 8 9 10"
 }
+
+identity_1: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        0 + a;
+        a + 0;
+        0 - a;
+        a - 0;
+        1 * a;
+        a * 1;
+        1 / a;
+        a / 1;
+    }
+    expect: {
+        0 + a;
+        a + 0;
+        0 - a;
+        +a;
+        +a;
+        +a;
+        1 / a;
+        +a;
+    }
+}
+
+identity_2: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        0 + !a;
+        !a + 0;
+        0 - !a;
+        !a - 0;
+        1 * !a;
+        !a * 1;
+        1 / !a;
+        !a / 1;
+    }
+    expect: {
+        +!a;
+        +!a;
+        0 - !a;
+        +!a;
+        +!a;
+        +!a;
+        1 / !a;
+        +!a;
+    }
+}
+
+identity_3: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        0 + --a;
+        --a + 0;
+        0 - --a;
+        --a - 0;
+        1 * --a;
+        --a * 1;
+        1 / --a;
+        --a / 1;
+    }
+    expect: {
+        --a;
+        --a;
+        0 - --a;
+        --a;
+        --a;
+        --a;
+        1 / --a;
+        --a;
+    }
+}
+
+issue_3653: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        console.log(0 - (console && 0));
+        console.log(0 + (0 - (console && 0)));
+        console.log(0 - (0 - (console && 0)));
+        console.log(1 * (0 - (console && 0)));
+        console.log(1 / (0 - (console && 0)));
+        console.log((0 - (console && 0)) + 0);
+        console.log((0 - (console && 0)) - 0);
+        console.log((0 - (console && 0)) * 1);
+        console.log((0 - (console && 0)) / 1);
+    }
+    expect: {
+        console.log(0 - (console && 0));
+        console.log(0 - (console && 0));
+        console.log(0 - (0 - (console && 0)));
+        console.log(0 - (console && 0));
+        console.log(1 / (0 - (console && 0)));
+        console.log(0 - (console && 0));
+        console.log(0 - (console && 0));
+        console.log(0 - (console && 0));
+        console.log(0 - (console && 0));
+    }
+    expect_stdout: [
+        "0",
+        "0",
+        "0",
+        "0",
+        "Infinity",
+        "0",
+        "0",
+        "0",
+        "0",
+    ]
+}
+
+issue_3655: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        console.log(0 + 0 * -[].length);
+        console.log(0 + (0 + 0 * -[].length));
+        console.log(0 - (0 + 0 * -[].length));
+        console.log(1 * (0 + 0 * -[].length));
+        console.log(1 / (0 + 0 * -[].length));
+        console.log((0 + 0 * -[].length) + 0);
+        console.log((0 + 0 * -[].length) - 0);
+        console.log((0 + 0 * -[].length) * 1);
+        console.log((0 + 0 * -[].length) / 1);
+    }
+    expect: {
+        console.log(0 + 0 * -[].length);
+        console.log(0 + 0 * -[].length);
+        console.log(0 - (0 + 0 * -[].length));
+        console.log(0 + 0 * -[].length);
+        console.log(1 / (0 + 0 * -[].length));
+        console.log(0 + 0 * -[].length);
+        console.log(0 + 0 * -[].length);
+        console.log(0 + 0 * -[].length);
+        console.log(0 + 0 * -[].length);
+    }
+    expect_stdout: [
+        "0",
+        "0",
+        "0",
+        "0",
+        "Infinity",
+        "0",
+        "0",
+        "0",
+        "0",
+    ]
+}
+
+issue_3676_1: {
+    options = {
+        evaluate: true,
+        unsafe_math: true,
+    }
+    input: {
+        var a = [];
+        console.log(false - (a - (a[1] = 42)));
+    }
+    expect: {
+        var a = [];
+        console.log(false - (a - (a[1] = 42)));
+    }
+    expect_stdout: "NaN"
+}
+
+issue_3676_2: {
+    options = {
+        evaluate: true,
+        unsafe_math: true,
+    }
+    input: {
+        var a;
+        console.log(false - ((a = []) - (a[1] = 42)));
+    }
+    expect: {
+        var a;
+        console.log(false - ((a = []) - (a[1] = 42)));
+    }
+    expect_stdout: "NaN"
+}
+
+issue_3682_1: {
+    options = {
+        evaluate: true,
+        unsafe_math: true,
+    }
+    input: {
+        var a = -0;
+        console.log(1 / (a - 1 + 1));
+    }
+    expect: {
+        var a = -0;
+        console.log(1 / (a - 1 + 1));
+    }
+    expect_stdout: "Infinity"
+}
+
+issue_3682_2: {
+    options = {
+        evaluate: true,
+        unsafe_math: true,
+    }
+    input: {
+        var a = -0, b = 1;
+        console.log(1 / (a - (b - b)));
+    }
+    expect: {
+        var a = -0, b = 1;
+        console.log(1 / (a - (b - b)));
+    }
+    expect_stdout: "-Infinity"
+}
+
+issue_3682_3: {
+    options = {
+        evaluate: true,
+        unsafe_math: true,
+    }
+    input: {
+        var a = -0, b = 1, c = -1;
+        console.log(1 / (a - (+b + +c)));
+    }
+    expect: {
+        var a = -0, b = 1, c = -1;
+        console.log(1 / (a - (+b + +c)));
+    }
+    expect_stdout: "-Infinity"
+}
+
+issue_3684: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        console.log(1 / (-1 * (0 & console) + 0));
+        console.log(1 / ((0 & console) / -1 + 0));
+    }
+    expect: {
+        console.log(1 / (-1 * (0 & console) + 0));
+        console.log(1 / ((0 & console) / -1 + 0));
+    }
+    expect_stdout: [
+        "Infinity",
+        "Infinity",
+    ]
+}
+
+issue_3695: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        var a = [];
+        console.log(+(a * (a[0] = false)));
+    }
+    expect: {
+        var a = [];
+        console.log(+(a * (a[0] = false)));
+    }
+    expect_stdout: "NaN"
+}

test/compress/properties.js

@@ -817,6 +817,29 @@ issue_2208_5: {
     expect_stdout: "42"
 }
 
+issue_2208_6: {
+    options = {
+        inline: true,
+        properties: true,
+        side_effects: true,
+    }
+    input: {
+        a = 42;
+        console.log(("FAIL", {
+            p: function() {
+                return this.a;
+            }
+        }.p)());
+    }
+    expect: {
+        a = 42;
+        console.log(function() {
+            return this.a;
+        }());
+    }
+    expect_stdout: "42"
+}
+
 issue_2256: {
     options = {
         side_effects: true,

test/compress/reduce_vars.js

@@ -2071,13 +2071,8 @@ issue_1670_6: {
     }
     expect: {
         (function(a) {
-            switch (1) {
+            a = 1;
-              case a = 1:
+            console.log(a);
-                console.log(a);
-                break;
-              default:
-                console.log(2);
-            }
         })(1);
     }
     expect_stdout: "1"
@@ -6801,3 +6796,80 @@ issue_3622: {
     }
     expect_stdout: "PASS"
 }
+
+issue_3631_1: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var c = 0;
+        L: do {
+            for (;;) continue L;
+            var b = 1;
+        } while (b && c++);
+        console.log(c);
+    }
+    expect: {
+        var c = 0;
+        L: do {
+            for (;;) continue L;
+            var b = 1;
+        } while (b && c++);
+        console.log(c);
+    }
+    expect_stdout: "0"
+}
+
+issue_3631_2: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        L: for (var a = 1; a--; console.log(b)) {
+            for (;;) continue L;
+            var b = "FAIL";
+        }
+    }
+    expect: {
+        L: for (var a = 1; a--; console.log(b)) {
+            for (;;) continue L;
+            var b = "FAIL";
+        }
+    }
+    expect_stdout: "undefined"
+}
+
+issue_3666: {
+    options = {
+        collapse_vars: true,
+        passes: 2,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        try {
+            var a = "FAIL";
+        } finally {
+            for (;!a;)
+                var c = a++;
+            var a = "PASS", b = c = "PASS";
+        }
+        console.log(a, b);
+    }
+    expect: {
+        try {
+            var a = "FAIL";
+        } finally {
+            for (;!a;)
+                a++;
+            var b = a = "PASS";
+        }
+        console.log(a, b);
+    }
+    expect_stdout: "PASS PASS"
+}

test/compress/regexp.js

@@ -186,3 +186,72 @@ issue_3434_3: {
         /\nfo\n[\n]o\bbb/;
     }
 }
+
+issue_3434_4: {
+    options = {
+        evaluate: true,
+        unsafe: true,
+    }
+    input: {
+        [
+            [ "", RegExp("") ],
+            [ "/", RegExp("/") ],
+            [ "//", RegExp("//") ],
+            [ "\/", RegExp("\\/") ],
+            [ "///", RegExp("///") ],
+            [ "/\/", RegExp("/\\/") ],
+            [ "\//", RegExp("\\//") ],
+            [ "\\/", RegExp("\\\\/") ],
+            [ "////", RegExp("////") ],
+            [ "//\/", RegExp("//\\/") ],
+            [ "/\//", RegExp("/\\//") ],
+            [ "/\\/", RegExp("/\\\\/") ],
+            [ "\///", RegExp("\\///") ],
+            [ "\/\/", RegExp("\\/\\/") ],
+            [ "\\//", RegExp("\\\\//") ],
+            [ "\\\/", RegExp("\\\\\\/") ],
+        ].forEach(function(test) {
+            console.log(test[1].test("\\"), test[1].test(test[0]));
+        });
+    }
+    expect: {
+        [
+            [ "", /(?:)/ ],
+            [ "/", /\// ],
+            [ "//", /\/\// ],
+            [ "/", /\// ],
+            [ "///", /\/\/\// ],
+            [ "//", /\/\// ],
+            [ "//", /\/\// ],
+            [ "\\/", /\\\// ],
+            [ "////", /\/\/\/\// ],
+            [ "///", /\/\/\// ],
+            [ "///", /\/\/\// ],
+            [ "/\\/", /\/\\\// ],
+            [ "///", /\/\/\// ],
+            [ "//", /\/\// ],
+            [ "\\//", /\\\/\// ],
+            [ "\\/", /\\\// ],
+        ].forEach(function(test) {
+            console.log(test[1].test("\\"), test[1].test(test[0]));
+        });
+    }
+    expect_stdout: [
+        "true true",
+        "false true",
+        "false true",
+        "false true",
+        "false true",
+        "false true",
+        "false true",
+        "false true",
+        "false true",
+        "false true",
+        "false true",
+        "false true",
+        "false true",
+        "false true",
+        "false true",
+        "false true",
+    ]
+}

test/compress/sequences.js

@@ -910,15 +910,23 @@ call: {
             console.log(this === b ? "bar" : "baz");
         };
         (a, b)();
+        (a, b).c();
         (a, b.c)();
+        (a, b)["c"]();
+        (a, b["c"])();
         (a, function() {
             console.log(this === a);
         })();
         new (a, b)();
+        new (a, b).c();
         new (a, b.c)();
+        new (a, b)["c"]();
+        new (a, b["c"])();
         new (a, function() {
             console.log(this === a);
         })();
+        console.log(typeof (a, b).c);
+        console.log(typeof (a, b)["c"]);
     }
     expect: {
         var a = function() {
@@ -931,23 +939,39 @@ call: {
             console.log(this === b ? "bar" : "baz");
         },
         b(),
+        b.c(),
         (a, b.c)(),
+        b["c"](),
+        (a, b["c"])(),
         function() {
             console.log(this === a);
         }(),
         new b(),
         new b.c(),
+        new b.c(),
+        new b["c"](),
+        new b["c"](),
         new function() {
             console.log(this === a);
-        }();
+        }(),
+        console.log((a, typeof b.c)),
+        console.log((a, typeof b["c"]));
     }
     expect_stdout: [
         "foo",
+        "bar",
+        "baz",
+        "bar",
         "baz",
         "true",
         "foo",
         "baz",
+        "baz",
+        "baz",
+        "baz",
         "false",
+        "function",
+        "function",
     ]
 }
 
@@ -1069,3 +1093,22 @@ issue_3490_2: {
     }
     expect_stdout: "PASS 42"
 }
+
+issue_3703: {
+    options = {
+        evaluate: true,
+        sequences: true,
+        unsafe: true,
+    }
+    input: {
+        var a = "FAIL";
+        while ((a = "PASS", 0).foo = 0);
+        console.log(a);
+    }
+    expect: {
+        var a = "FAIL";
+        while (a = "PASS", (0).foo = 0);
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}

test/compress/side_effects.js

@@ -0,0 +1,277 @@
+accessor: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        ({
+            get a() {},
+            set a(v){
+                this.b = 2;
+            },
+            b: 1
+        });
+    }
+    expect: {}
+}
+
+issue_2233_1: {
+    options = {
+        pure_getters: "strict",
+        side_effects: true,
+        unsafe: true,
+    }
+    input: {
+        Array.isArray;
+        Boolean;
+        console.log;
+        Date;
+        decodeURI;
+        decodeURIComponent;
+        encodeURI;
+        encodeURIComponent;
+        Error.name;
+        escape;
+        eval;
+        EvalError;
+        Function.length;
+        isFinite;
+        isNaN;
+        JSON;
+        Math.random;
+        Number.isNaN;
+        parseFloat;
+        parseInt;
+        RegExp;
+        Object.defineProperty;
+        String.fromCharCode;
+        RangeError;
+        ReferenceError;
+        SyntaxError;
+        TypeError;
+        unescape;
+        URIError;
+    }
+    expect: {}
+    expect_stdout: true
+}
+
+global_timeout_and_interval_symbols: {
+    options = {
+        pure_getters: "strict",
+        side_effects: true,
+        unsafe: true,
+    }
+    input: {
+        // These global symbols do not exist in the test sandbox
+        // and must be tested separately.
+        clearInterval;
+        clearTimeout;
+        setInterval;
+        setTimeout;
+    }
+    expect: {}
+}
+
+issue_2233_2: {
+    options = {
+        pure_getters: "strict",
+        reduce_funcs: true,
+        reduce_vars: true,
+        side_effects: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        var RegExp;
+        Array.isArray;
+        RegExp;
+        UndeclaredGlobal;
+        function foo() {
+            var Number;
+            AnotherUndeclaredGlobal;
+            Math.sin;
+            Number.isNaN;
+        }
+    }
+    expect: {
+        var RegExp;
+        UndeclaredGlobal;
+        function foo() {
+            var Number;
+            AnotherUndeclaredGlobal;
+            Number.isNaN;
+        }
+    }
+}
+
+issue_2233_3: {
+    options = {
+        pure_getters: "strict",
+        reduce_funcs: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        var RegExp;
+        Array.isArray;
+        RegExp;
+        UndeclaredGlobal;
+        function foo() {
+            var Number;
+            AnotherUndeclaredGlobal;
+            Math.sin;
+            Number.isNaN;
+        }
+    }
+    expect: {
+        UndeclaredGlobal;
+    }
+}
+
+global_fns: {
+    options = {
+        side_effects: true,
+        unsafe: true,
+    }
+    input: {
+        Boolean(1, 2);
+        decodeURI(1, 2);
+        decodeURIComponent(1, 2);
+        Date(1, 2);
+        encodeURI(1, 2);
+        encodeURIComponent(1, 2);
+        Error(1, 2);
+        escape(1, 2);
+        EvalError(1, 2);
+        isFinite(1, 2);
+        isNaN(1, 2);
+        Number(1, 2);
+        Object(1, 2);
+        parseFloat(1, 2);
+        parseInt(1, 2);
+        RangeError(1, 2);
+        ReferenceError(1, 2);
+        String(1, 2);
+        SyntaxError(1, 2);
+        TypeError(1, 2);
+        unescape(1, 2);
+        URIError(1, 2);
+        try {
+            Function(1, 2);
+        } catch (e) {
+            console.log(e.name);
+        }
+        try {
+            RegExp(1, 2);
+        } catch (e) {
+            console.log(e.name);
+        }
+        try {
+            Array(NaN);
+        } catch (e) {
+            console.log(e.name);
+        }
+    }
+    expect: {
+        try {
+            Function(1, 2);
+        } catch (e) {
+            console.log(e.name);
+        }
+        try {
+            RegExp(1, 2);
+        } catch (e) {
+            console.log(e.name);
+        }
+        try {
+            Array(NaN);
+        } catch (e) {
+            console.log(e.name);
+        }
+    }
+    expect_stdout: [
+        "SyntaxError",
+        "SyntaxError",
+        "RangeError",
+    ]
+}
+
+unsafe_builtin_1: {
+    options = {
+        side_effects: true,
+        unsafe: true,
+    }
+    input: {
+        (!w).constructor(x);
+        Math.abs(y);
+        [ 1, 2, z ].valueOf();
+    }
+    expect: {
+        w, x;
+        y;
+        z;
+    }
+}
+
+unsafe_builtin_2: {
+    options = {
+        side_effects: true,
+        unsafe: true,
+    }
+    input: {
+        var o = {};
+        constructor.call(o, 42);
+        __defineGetter__.call(o, "foo", function() {
+            return o.p;
+        });
+        __defineSetter__.call(o, void 0, function(a) {
+            o.p = a;
+        });
+        console.log(typeof o, o.undefined = "PASS", o.foo);
+    }
+    expect: {
+        var o = {};
+        constructor.call(o, 42);
+        __defineGetter__.call(o, "foo", function() {
+            return o.p;
+        });
+        __defineSetter__.call(o, void 0, function(a) {
+            o.p = a;
+        });
+        console.log(typeof o, o.undefined = "PASS", o.foo);
+    }
+    expect_stdout: "object PASS PASS"
+}
+
+unsafe_string_replace: {
+    options = {
+        side_effects: true,
+        unsafe: true,
+    }
+    input: {
+        "foo".replace("f", function() {
+            console.log("PASS");
+        });
+    }
+    expect: {
+        "foo".replace("f", function() {
+            console.log("PASS");
+        });
+    }
+    expect_stdout: "PASS"
+}
+
+drop_value: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        (1, [2, foo()], 3, {a:1, b:bar()});
+    }
+    expect: {
+        foo(), bar();
+    }
+}

test/compress/transform.js

@@ -103,6 +103,7 @@ if_return: {
         booleans: true,
         conditionals: true,
         if_return: true,
+        passes: 2,
         sequences: true,
         side_effects: true,
     }

test/compress/unicode.js

@@ -16,6 +16,81 @@ unicode_parse_variables: {
     }
 }
 
+unicode_escaped_identifier: {
+    input: {
+        var \u0061 = "\ud800\udc00";
+        console.log(a);
+    }
+    expect_exact: 'var a="\ud800\udc00";console.log(a);'
+    expect_stdout: "\ud800\udc00"
+}
+
+unicode_identifier_ascii_only: {
+    beautify = {
+        ascii_only: true,
+    }
+    input: {
+        var \u0061 = "testing \udbc4\udd11";
+        var bar = "h\u0065llo";
+        console.log(a, \u0062\u0061r);
+    }
+    expect_exact: 'var a="testing \\udbc4\\udd11";var bar="hello";console.log(a,bar);'
+    expect_stdout: "testing \udbc4\udd11 hello"
+}
+
+unicode_string_literals: {
+    beautify = {
+        ascii_only: true,
+    }
+    input: {
+        var a = "6 length unicode character: \udbc4\udd11";
+        console.log(\u0061);
+    }
+    expect_exact: 'var a="6 length unicode character: \\udbc4\\udd11";console.log(a);'
+    expect_stdout: "6 length unicode character: \udbc4\udd11"
+}
+
+check_escape_style: {
+    beautify = {
+        ascii_only: true,
+    }
+    input: {
+        var a = "\x01";
+        var \ua0081 = "\x10"; // \u0081 only in ID_Continue
+        var \u0100 = "\u0100";
+        var \u1000 = "\u1000";
+        var \u1000 = "\ud800\udc00";
+        var \u3f80 = "\udbc0\udc00";
+        console.log(\u0061, \ua0081, \u0100, \u1000, \u3f80);
+    }
+    expect_exact: 'var a="\\x01";var \\ua0081="\\x10";var \\u0100="\\u0100";var \\u1000="\\u1000";var \\u1000="\\ud800\\udc00";var \\u3f80="\\udbc0\\udc00";console.log(a,\\ua0081,\\u0100,\\u1000,\\u3f80);'
+    expect_stdout: "\u0001 \u0010 \u0100 \ud800\udc00 \udbc0\udc00"
+}
+
+escape_non_escaped_identifier: {
+    beautify = {
+        ascii_only: true,
+    }
+    input: {
+        var µþ = "µþ";
+        console.log(\u00b5þ);
+    }
+    expect_exact: 'var \\u00b5\\u00fe="\\xb5\\xfe";console.log(\\u00b5\\u00fe);'
+    expect_stdout: "µþ"
+}
+
+non_escape_2_non_escape: {
+    beautify = {
+        ascii_only: false,
+    }
+    input: {
+        var µþ = "µþ";
+        console.log(\u00b5þ);
+    }
+    expect_exact: 'var µþ="µþ";console.log(µþ);'
+    expect_stdout: "µþ"
+}
+
 issue_2242_1: {
     beautify = {
         ascii_only: false,
@@ -24,6 +99,7 @@ issue_2242_1: {
         console.log("\ud83d", "\ude00", "\ud83d\ude00", "\ud83d@\ude00");
     }
     expect_exact: 'console.log("\\ud83d","\\ude00","\ud83d\ude00","\\ud83d@\\ude00");'
+    expect_stdout: "\ud83d \ude00 \ud83d\ude00 \ud83d@\ude00"
 }
 
 issue_2242_2: {
@@ -34,6 +110,7 @@ issue_2242_2: {
         console.log("\ud83d", "\ude00", "\ud83d\ude00", "\ud83d@\ude00");
     }
     expect_exact: 'console.log("\\ud83d","\\ude00","\\ud83d\\ude00","\\ud83d@\\ude00");'
+    expect_stdout: "\ud83d \ude00 \ud83d\ude00 \ud83d@\ude00"
 }
 
 issue_2242_3: {
@@ -44,6 +121,7 @@ issue_2242_3: {
         console.log("\ud83d" + "\ude00", "\ud83d" + "@" + "\ude00");
     }
     expect_exact: 'console.log("\\ud83d"+"\\ude00","\\ud83d"+"@"+"\\ude00");'
+    expect_stdout: "\ud83d\ude00 \ud83d@\ude00"
 }
 
 issue_2242_4: {
@@ -54,6 +132,7 @@ issue_2242_4: {
         console.log("\ud83d" + "\ude00", "\ud83d" + "@" + "\ude00");
     }
     expect_exact: 'console.log("\ud83d\ude00","\\ud83d@\\ude00");'
+    expect_stdout: "\ud83d\ude00 \ud83d@\ude00"
 }
 
 issue_2569: {

test/exports.js

@@ -1,6 +1,7 @@
 exports["Compressor"] = Compressor;
 exports["defaults"] = defaults;
 exports["JS_Parse_Error"] = JS_Parse_Error;
+exports["List"] = List;
 exports["mangle_properties"] = mangle_properties;
 exports["minify"] = minify;
 exports["OutputStream"] = OutputStream;

test/input/issue-1482/beautify.js

@@ -0,0 +1,17 @@
+if (x) foo();
+
+if (x) foo(); else baz();
+
+if (x) foo(); else if (y) bar(); else baz();
+
+if (x) if (y) foo(); else bar(); else baz();
+
+if (x) foo(); else if (y) bar(); else if (z) baz(); else moo();
+
+function f() {
+    if (x) foo();
+    if (x) foo(); else baz();
+    if (x) foo(); else if (y) bar(); else baz();
+    if (x) if (y) foo(); else bar(); else baz();
+    if (x) foo(); else if (y) bar(); else if (z) baz(); else moo();
+}

test/input/issue-1482/default.js

@@ -1,17 +1 @@
-if (x) foo();
+if(x)foo();if(x)foo();else baz();if(x)foo();else if(y)bar();else baz();if(x)if(y)foo();else bar();else baz();if(x)foo();else if(y)bar();else if(z)baz();else moo();function f(){if(x)foo();if(x)foo();else baz();if(x)foo();else if(y)bar();else baz();if(x)if(y)foo();else bar();else baz();if(x)foo();else if(y)bar();else if(z)baz();else moo()}
-
-if (x) foo(); else baz();
-
-if (x) foo(); else if (y) bar(); else baz();
-
-if (x) if (y) foo(); else bar(); else baz();
-
-if (x) foo(); else if (y) bar(); else if (z) baz(); else moo();
-
-function f() {
-    if (x) foo();
-    if (x) foo(); else baz();
-    if (x) foo(); else if (y) bar(); else baz();
-    if (x) if (y) foo(); else bar(); else baz();
-    if (x) foo(); else if (y) bar(); else if (z) baz(); else moo();
-}

test/input/reduce/label.js

@@ -0,0 +1,9 @@
+var o = this;
+
+for (var k in o) L17060: {
+    a++;
+}
+
+var a;
+
+console.log(k);

test/input/reduce/label.reduced.js

@@ -0,0 +1,16 @@
+var o = this;
+
+for (var k in o) {
+    0;
+}
+
+var a;
+
+console.log(k);
+// output: a
+// 
+// minify: k
+// 
+// options: {
+//   "mangle": false
+// }

test/input/reduce/unsafe_math.js

@@ -0,0 +1,18 @@
+var _calls_ = 10, a = 100, b = 10, c = 0;
+
+function f0(b_1, a, undefined_2) {
+    a++ + ++b;
+    {
+        var expr2 = (b + 1 - .1 - .1 - .1 || a || 3).toString();
+        L20778: for (var key2 in expr2) {
+            (c = c + 1) + [ --b + b_1, typeof f0 == "function" && --_calls_ >= 0 && f0(--b + typeof (undefined_2 = 1 === 1 ? a : b), --b + {
+                c: (c = c + 1) + null
+            }, a++ + (typeof f0 == "function" && --_calls_ >= 0 && f0(typeof (c = 1 + c, 3 / "a" * ("c" >>> 23..toString()) >= (b_1 && (b_1[(c = c + 1) + a--] = (- -0,
+            true + {})))), 3, 25))), 1 === 1 ? a : b ];
+        }
+    }
+}
+
+var a_1 = f0([ , 0 ].length === 2);
+
+console.log(null, a, b, c, Infinity, NaN, undefined);

test/input/reduce/unsafe_math.reduced.js

@@ -0,0 +1,19 @@
+var b = 0;
+
+var expr2 = (0 - 1 - .1 - .1).toString();
+
+for (var key2 in expr2) {
+    --b;
+}
+
+console.log(b);
+// output: -19
+// 
+// minify: -4
+// 
+// options: {
+//   "compress": {
+//     "unsafe_math": true
+//   },
+//   "mangle": false
+// }

test/mocha.js

@@ -1,7 +1,7 @@
 var fs = require("fs");
 
 var config = {
-    limit: 5000,
+    limit: 10000,
     timeout: function(limit) {
         this.limit = limit;
     }
@@ -55,11 +55,11 @@ process.nextTick(function run() {
         var elapsed = Date.now();
         var timer;
         var done = function() {
-            reset();
             elapsed = Date.now() - elapsed;
             if (elapsed > task.limit) {
                 throw new Error("Timed out: " + elapsed + "ms > " + task.limit + "ms");
             }
+            reset();
             log_titles(console.log, task.titles, green('\u221A '));
             process.nextTick(run);
         };

test/mocha/cli.js

@@ -176,7 +176,7 @@ describe("bin/uglifyjs", function() {
         var command = uglifyjscmd + ' test/input/issue-1482/input.js -b';
         exec(command, function(err, stdout) {
             if (err) throw err;
-            assert.strictEqual(stdout, read("test/input/issue-1482/default.js"));
+            assert.strictEqual(stdout, read("test/input/issue-1482/beautify.js"));
             done();
         });
     });
@@ -188,6 +188,22 @@ describe("bin/uglifyjs", function() {
             done();
         });
     });
+    it("Should work with `--output-opts`", function(done) {
+        var command = uglifyjscmd + ' test/input/issue-1482/input.js -O';
+        exec(command, function(err, stdout) {
+            if (err) throw err;
+            assert.strictEqual(stdout, read("test/input/issue-1482/default.js"));
+            done();
+        });
+    });
+    it("Should fail when both --beautify & --output-opts are specified", function(done) {
+        var command = uglifyjscmd + " test/input/issue-520/input.js -bO";
+        exec(command, function(err, stdout, stderr) {
+            assert.ok(err);
+            assert.strictEqual(stderr, "ERROR: --beautify cannot be used with --output-opts\n");
+            done();
+        });
+    });
     it("Should process inline source map", function(done) {
         var command = [
             uglifyjscmd,

test/mocha/directives.js

@@ -69,13 +69,13 @@ describe("Directives", function() {
             ],
             [
                 '"use \\\nstrict";"use strict";',
-                [],
+                [ "use strict" ],
-                [ "use strict", "use\nstrict", "use \nstrict", "use asm" ]
+                [ "use\nstrict", "use \nstrict", "use asm" ]
             ],
             [
                 '"\\76";',
-                [],
+                [ "\\76" ],
-                [ ">", "\\76" ]
+                [ ">" ]
             ],
             [
                 // no ; or newline
@@ -106,13 +106,13 @@ describe("Directives", function() {
             ],
             [
                 'function foo() {"use \\\nstrict";"use strict";',
-                [],
+                [ "use strict" ],
-                [ "use strict", "use\nstrict", "use \nstrict", "use asm" ]
+                [ "use\nstrict", "use \nstrict", "use asm" ]
             ],
             [
                 'var foo = function() {"\\76";',
-                [],
+                [ "\\76" ],
-                [ ">", "\\76" ]
+                [ ">" ]
             ],
             [
                 'var foo = function() {"use strict"', // no ; or newline
@@ -156,21 +156,24 @@ describe("Directives", function() {
             });
         });
     });
-    it("Should test EXPECT_DIRECTIVE RegExp", function() {
+    it("Should print semicolon to separate strings from directives", function() {
         [
-            [ "", true ],
+            [ "", ';"";' ],
-            [ "'test';", true ],
+            [ '"test";', '"test";;"";' ],
-            [ "'test';;", true ],
+            [ '"test";;', '"test";;"";' ],
-            [ "'tests';\n", true ],
+            [ '"tests";\n', '"tests";;"";' ],
-            [ "'tests'", false ],
+            [ '"tests"', '"tests";;"";' ],
-            [ "'tests';   \n\t", true ],
+            [ '"tests";   \n\t', '"tests";;"";' ],
-            [ "'tests';\n\n", true ],
+            [ '"tests";\n\n', '"tests";;"";' ],
-            [ "\n\n\"use strict\";\n\n", true ],
+            [ '\n\n"use strict";\n\n', '"use strict";;"";' ],
         ].forEach(function(test) {
+            var ast = UglifyJS.parse(test[0]);
+            ast.body.push(new UglifyJS.AST_SimpleStatement({
+                body: new UglifyJS.AST_String({ value: "" })
+            }));
             var out = UglifyJS.OutputStream();
-            out.print(test[0]);
+            ast.print(out);
-            out.print_string("", null, true);
+            assert.strictEqual(out.get(), test[1], test[0]);
-            assert.strictEqual(out.get() === test[0] + ';""', test[1], test[0]);
         });
     });
     it("Should only print 2 semicolons spread over 2 lines in beautify mode", function() {
@@ -178,8 +181,8 @@ describe("Directives", function() {
             '"use strict";',
             "'use strict';",
             '"use strict";',
-            '"use strict";;',
+            '"use strict";',
-            "'use strict';",
+            ";'use strict';",
             "console.log('use strict');"
         ].join(""), {
             compress: false,
@@ -201,19 +204,23 @@ describe("Directives", function() {
     it("Should not add double semicolons in non-scoped block statements to avoid strings becoming directives", function() {
         [
             [
-                '{"use\x20strict"}',
+                '"use strict";"use\\x20strict";',
+                '"use strict";"use\\x20strict";'
+            ],
+            [
+                '{"use\\x20strict"}',
                 '{"use strict"}'
             ],
             [
-                'function foo(){"use\x20strict";}', // Valid place for directives
+                'function foo(){"use\\x20strict";}', // Valid place for directives
-                'function foo(){"use strict"}'
+                'function foo(){"use\\x20strict"}'
             ],
             [
-                'try{"use\x20strict"}catch(e){}finally{"use\x20strict"}',
+                'try{"use\\x20strict"}catch(e){}finally{"use\\x20strict"}',
                 'try{"use strict"}catch(e){}finally{"use strict"}'
             ],
             [
-                'if(1){"use\x20strict"} else {"use strict"}',
+                'if(1){"use\\x20strict"} else {"use strict"}',
                 'if(1){"use strict"}else{"use strict"}'
             ]
         ].forEach(function(test) {
@@ -225,16 +232,6 @@ describe("Directives", function() {
             assert.strictEqual(result.code, test[1], test[0]);
         });
     });
-    it("Should add double semicolon when relying on automatic semicolon insertion", function() {
-        var result = UglifyJS.minify('"use strict";"use\\x20strict";', {
-            compress: false,
-            output: {
-                semicolons: false
-            }
-        });
-        if (result.error) throw result.error;
-        assert.strictEqual(result.code, '"use strict";;"use strict"\n');
-    });
     it("Should check quote style of directives", function() {
         [
             // 0. Prefer double quotes, unless string contains more double quotes than single quotes
@@ -249,9 +246,9 @@ describe("Directives", function() {
                 '"use strict";'
             ],
             [
-                '"\\\'use strict\\\'";', // Not a directive as it contains quotes
+                '"\\\'use strict\\\'";',
                 0,
-                ';"\'use strict\'";',
+                '"\\\'use strict\\\'";',
             ],
             [
                 "'\"use strict\"';",
@@ -273,7 +270,7 @@ describe("Directives", function() {
                 '"\'use strict\'";',
                 1,
                 // Intentionally causes directive breakage at cost of less logic, usage should be rare anyway
-                "'\\'use strict\\'';",
+                '"\'use strict\'";',
             ],
             [
                 "'\\'use strict\\'';", // Not a valid directive
@@ -305,7 +302,7 @@ describe("Directives", function() {
                 "'\"use strict\"';",
                 2,
                 // Intentionally causes directive breakage at cost of less logic, usage should be rare anyway
-                '"\\\"use strict\\\"";',
+                "'\"use strict\"';",
             ],
             [
                 '"\\"use strict\\"";', // Not a valid directive
@@ -353,8 +350,7 @@ describe("Directives", function() {
             [
                 // Nothing gets optimised in the compressor because "use asm" is the first statement
                 '"use asm";"use\\x20strict";1+1;',
-                // Yet, the parser noticed that "use strict" wasn't a directive
+                '"use asm";"use\\x20strict";1+1;'
-                '"use asm";;"use strict";1+1;',
             ],
             [
                 'function f(){ "use strict" }',

test/mocha/reduce.js

@@ -0,0 +1,167 @@
+var assert = require("assert");
+var exec = require("child_process").exec;
+var fs = require("fs");
+var reduce_test = require("../reduce");
+var semver = require("semver");
+
+function read(path) {
+    return fs.readFileSync(path, "utf8");
+}
+
+describe("test/reduce.js", function() {
+    this.timeout(60000);
+    it("Should reduce test case", function() {
+        var result = reduce_test(read("test/input/reduce/unsafe_math.js"), {
+            compress: {
+                unsafe_math: true,
+            },
+            mangle: false,
+        }, {
+            verbose: false,
+        });
+        if (result.error) throw result.error;
+        assert.strictEqual(result.code, read("test/input/reduce/unsafe_math.reduced.js"));
+    });
+    it("Should eliminate unreferenced labels", function() {
+        var result = reduce_test(read("test/input/reduce/label.js"), {
+            mangle: false,
+        }, {
+            verbose: false,
+        });
+        if (result.error) throw result.error;
+        assert.strictEqual(result.code, read("test/input/reduce/label.reduced.js"));
+    });
+    it("Should handle test cases with --toplevel", function() {
+        var result = reduce_test([
+            "var Infinity = 42;",
+            "console.log(Infinity);",
+        ].join("\n"), {
+            toplevel: true,
+        });
+        if (result.error) throw result.error;
+        assert.strictEqual(result.code, [
+            "// Can't reproduce test failure with minify options provided:",
+            "// {",
+            '//   "toplevel": true',
+            "// }",
+        ].join("\n"));
+    });
+    it("Should handle test result of NaN", function() {
+        var result = reduce_test("throw 0 / 0;");
+        if (result.error) throw result.error;
+        assert.strictEqual(result.code, [
+            "// Can't reproduce test failure with minify options provided:",
+            "// {",
+            '//   "compress": {},',
+            '//   "mangle": false',
+            "// }",
+        ].join("\n"));
+    });
+    it("Should print correct output for irreducible test case", function() {
+        var result = reduce_test([
+            "console.log(function f(a) {",
+            "    return f.length;",
+            "}());",
+        ].join("\n"), {
+            compress: {
+                keep_fargs: false,
+            },
+            mangle: false,
+        });
+        if (result.error) throw result.error;
+        assert.strictEqual(result.code, [
+            "console.log(function f(a) {",
+            "    return f.length;",
+            "}());",
+            "// output: 1",
+            "// ",
+            "// minify: 0",
+            "// ",
+            "// options: {",
+            '//   "compress": {',
+            '//     "keep_fargs": false',
+            "//   },",
+            '//   "mangle": false',
+            "// }",
+        ].join("\n"));
+    });
+    it("Should fail when invalid option is supplied", function() {
+        var result = reduce_test("", {
+            compress: {
+                unsafe_regex: true,
+            },
+        });
+        var err = result.error;
+        assert.ok(err instanceof Error);
+        assert.strictEqual(err.stack.split(/\n/)[0], "DefaultsError: `unsafe_regex` is not a supported option");
+    });
+    it("Should report on test case with invalid syntax", function() {
+        var result = reduce_test("var 0 = 1;");
+        var err = result.error;
+        assert.ok(err instanceof Error);
+        assert.strictEqual(err.stack.split(/\n/)[0], "SyntaxError: Name expected");
+    });
+    it("Should format multi-line output correctly", function() {
+        var code = [
+            "var a = 0;",
+            "",
+            "for (var b in [ 1, 2, 3 ]) {",
+            "    a = +a + 1 - .2;",
+            "    console.log(a);",
+            "}",
+        ].join("\n");
+        var result = reduce_test(code, {
+            compress: {
+                unsafe_math: true,
+            },
+            mangle: false,
+        });
+        if (result.error) throw result.error;
+        assert.strictEqual(result.code, [
+            code,
+            "// output: 0.8",
+            "// 1.6",
+            "// 2.4",
+            "// ",
+            "// minify: 0.8",
+            "// 1.6",
+            "// 2.4000000000000004",
+            "// ",
+            "// options: {",
+            '//   "compress": {',
+            '//     "unsafe_math": true',
+            "//   },",
+            '//   "mangle": false',
+            "// }",
+        ].join("\n"));
+    });
+    it("Should reduce infinite loops with reasonable performance", function() {
+        if (semver.satisfies(process.version, "0.10")) return;
+        this.timeout(120000);
+        var code = [
+            "var a = 9007199254740992, b = 1;",
+            "",
+            "while (a++ + (1 - b) < a) {",
+            "    0;",
+            "}",
+        ].join("\n");
+        var result = reduce_test(code, {
+            compress: {
+                unsafe_math: true,
+            },
+            mangle: false,
+        });
+        if (result.error) throw result.error;
+        assert.strictEqual(result.code.replace(/ timed out after [0-9]+ms/, " timed out."), [
+            code,
+            "// output: ",
+            "// minify: Error: Script execution timed out.",
+            "// options: {",
+            '//   "compress": {',
+            '//     "unsafe_math": true',
+            "//   },",
+            '//   "mangle": false',
+            "// }",
+        ].join("\n"));
+    });
+});

test/mocha/string-literal.js

@@ -59,13 +59,13 @@ describe("String literals", function() {
 
     it("Should not throw error outside strict mode if string contains escaped octalIntegerLiteral", function() {
         var tests = [
-            ['"\\76";', ';">";'],
+            [ ';"\\76";', ';">";' ],
-            ['"\\0"', '"\\0";'],
+            [ ';"\\0";', ';"\\0";' ],
-            ['"\\08"', '"\\x008";'],
+            [ ';"\\08"', ';"\\x008";' ],
-            ['"\\008"', '"\\x008";'],
+            [ ';"\\008"', ';"\\x008";' ],
-            ['"\\0008"', '"\\x008";'],
+            [ ';"\\0008"', ';"\\x008";' ],
-            ['"use strict" === "use strict";\n"\\76";', '"use strict"==="use strict";">";'],
+            [ ';"use\\\n strict";\n"\\07";', ';"use strict";"\07";' ],
-            ['"use\\\n strict";\n"\\07";', ';"use strict";"\07";']
+            [ '"use strict" === "use strict";\n"\\76";', '"use strict"==="use strict";">";' ],
         ];
 
         for (var test in tests) {
@@ -75,8 +75,8 @@ describe("String literals", function() {
     });
 
     it("Should not throw error when digit is 8 or 9", function() {
-        assert.equal(UglifyJS.parse('"use strict";"\\08"').print_to_string(), '"use strict";"\\x008";');
+        assert.equal(UglifyJS.parse('"use strict";;"\\08"').print_to_string(), '"use strict";;"\\x008";');
-        assert.equal(UglifyJS.parse('"use strict";"\\09"').print_to_string(), '"use strict";"\\x009";');
+        assert.equal(UglifyJS.parse('"use strict";;"\\09"').print_to_string(), '"use strict";;"\\x009";');
     });
 
     it("Should not unescape unpaired surrogates", function() {
@@ -93,7 +93,7 @@ describe("String literals", function() {
         for (; i <= 0xFFFF; i++) {
             code.push("\\u" + i.toString(16));
         }
-        code = '"' + code.join() + '"';
+        code = ';"' + code.join() + '"';
         var normal = UglifyJS.minify(code, {
             compress: false,
             mangle: false,

test/reduce.js

@@ -0,0 +1,564 @@
+var crypto = require("crypto");
+var U = require("./node");
+var List = U.List;
+var os = require("os");
+var sandbox = require("./sandbox");
+
+// Reduce a ufuzz-style `console.log` based test case by iteratively replacing
+// AST nodes with various permutations. Each AST_Statement in the tree is also
+// speculatively dropped to determine whether it is needed.  If the altered
+// tree and the last known good tree produce the same non-nil error-free output
+// after being run, then the permutation survives to the next generation and
+// is the basis for subsequent iterations.  The test case is reduced as a
+// consequence of complex expressions being replaced with simpler ones.
+// This function assumes that the testcase will not result in a parse or
+// runtime Error.  Note that a reduced test case will have different runtime
+// output - it is not functionally equivalent to the original. The only criteria
+// is that once the generated reduced test case is run without minification, it
+// will produce different output from the code minified with `minify_options`.
+// Returns a `minify` result object with an additonal boolean property `reduced`.
+
+module.exports = function reduce_test(testcase, minify_options, reduce_options) {
+    if (testcase instanceof U.AST_Node) testcase = testcase.print_to_string();
+    minify_options = minify_options || { compress: {}, mangle: false };
+    reduce_options = reduce_options || {};
+    var max_iterations = reduce_options.max_iterations || 1000;
+    var max_timeout = reduce_options.max_timeout || 10000;
+    var verbose = reduce_options.verbose;
+    var minify_options_json = JSON.stringify(minify_options, null, 2);
+    var result_cache = Object.create(null);
+    // the initial timeout to assess the viability of the test case must be large
+    var differs = producesDifferentResultWhenMinified(result_cache, testcase, minify_options, max_timeout);
+
+    if (verbose) {
+        console.error("// Node.js " + process.version + " on " + os.platform() + " " + os.arch());
+    }
+    if (!differs) {
+        // same stdout result produced when minified
+        return {
+            code: "// Can't reproduce test failure with minify options provided:"
+                + "\n// " + to_comment(minify_options_json)
+        };
+    } else if (differs.timed_out) {
+        return {
+            code: "// Can't reproduce test failure within " + max_timeout + "ms:"
+                + "\n// " + to_comment(minify_options_json)
+        };
+    } else if (differs.error) {
+        return differs;
+    } else {
+        max_timeout = Math.min(100 * differs.elapsed, max_timeout);
+        // Replace expressions with constants that will be parsed into
+        // AST_Nodes as required.  Each AST_Node has its own permutation count,
+        // so these replacements can't be shared.
+        // Although simpler replacements are generally faster and better,
+        // feel free to experiment with a different replacement set.
+        var REPLACEMENTS = [
+            // "null", "''", "false", "'foo'", "undefined", "9",
+            "1", "0",
+        ];
+
+        // There's a relationship between each node's _permute counter and
+        // REPLACEMENTS.length which is why fractional _permutes were needed.
+        // One could scale all _permute operations by a factor of `steps`
+        // to only deal with integer operations, but this works well enough.
+        var steps = 4;        // must be a power of 2
+        var step = 1 / steps; // 0.25 is exactly representable in floating point
+
+        var tt = new U.TreeTransformer(function(node, descend, in_list) {
+            if (CHANGED) return;
+
+            // quick ignores
+            if (node instanceof U.AST_Accessor) return;
+            if (node instanceof U.AST_Directive) return;
+            if (node instanceof U.AST_Label) return;
+            if (node instanceof U.AST_LabelRef) return;
+            if (!in_list && node instanceof U.AST_SymbolDeclaration) return;
+            if (node instanceof U.AST_Toplevel) return;
+
+            var parent = tt.parent();
+
+            // ensure that the _permute prop is a number.
+            // can not use `node.start._permute |= 0;` as it will erase fractional part.
+            if (typeof node.start._permute === "undefined") node.start._permute = 0;
+
+            // if node reached permutation limit - skip over it.
+            // no structural AST changes before this point.
+            if (node.start._permute >= REPLACEMENTS.length) return;
+
+            if (parent instanceof U.AST_Assign
+                    && parent.left === node
+                || parent instanceof U.AST_Unary
+                    && parent.expression === node
+                    && ["++", "--", "delete"].indexOf(parent.operator) >= 0) {
+                // ignore lvalues
+                return;
+            }
+            if ((parent instanceof U.AST_For || parent instanceof U.AST_ForIn)
+                && parent.init === node && node instanceof U.AST_Var) {
+                // preserve for (var ...)
+                return node;
+            }
+
+            // node specific permutations with no parent logic
+
+            if (node instanceof U.AST_Array) {
+                var expr = node.elements[0];
+                if (expr && !(expr instanceof U.AST_Hole)) {
+                    node.start._permute++;
+                    CHANGED = true;
+                    return expr;
+                }
+            }
+            else if (node instanceof U.AST_Binary) {
+                CHANGED = true;
+                return [
+                    node.left,
+                    node.right,
+                ][ ((node.start._permute += step) * steps | 0) % 2 ];
+            }
+            else if (node instanceof U.AST_Catch || node instanceof U.AST_Finally) {
+                // drop catch or finally block
+                node.start._permute++;
+                CHANGED = true;
+                return null;
+            }
+            else if (node instanceof U.AST_Conditional) {
+                CHANGED = true;
+                return [
+                    node.condition,
+                    node.consequent,
+                    node.alternative,
+                ][ ((node.start._permute += step) * steps | 0) % 3 ];
+            }
+            else if (node instanceof U.AST_BlockStatement) {
+                if (in_list) {
+                    node.start._permute++;
+                    CHANGED = true;
+                    return List.splice(node.body);
+                }
+            }
+            else if (node instanceof U.AST_Call) {
+                var expr = [
+                    node.expression,
+                    node.args[0],
+                    null,  // intentional
+                ][ ((node.start._permute += step) * steps | 0) % 3 ];
+                if (expr) {
+                    CHANGED = true;
+                    return expr;
+                }
+                if (node.expression instanceof U.AST_Function) {
+                    // hoist and return expressions from the IIFE function expression
+                    var body = node.expression.body;
+                    node.expression.body = [];
+                    var seq = [];
+                    body.forEach(function(node) {
+                        var expr = expr instanceof U.AST_Exit ? node.value : node.body;
+                        if (expr instanceof U.AST_Node && !is_statement(expr)) {
+                            // collect expressions from each statements' body
+                            seq.push(expr);
+                        }
+                    });
+                    CHANGED = true;
+                    return to_sequence(seq);
+                }
+            }
+            else if (node instanceof U.AST_Defun) {
+                switch (((node.start._permute += step) * steps | 0) % 2) {
+                  case 0:
+                    CHANGED = true;
+                    return List.skip;
+                  case 1:
+                    if (!has_exit(node)) {
+                        // hoist function declaration body
+                        var body = node.body;
+                        node.body = [];
+                        body.push(node); // retain function with empty body to be dropped later
+                        CHANGED = true;
+                        return List.splice(body);
+                    }
+                }
+            }
+            else if (node instanceof U.AST_DWLoop) {
+                var expr = [
+                    node.condition,
+                    node.body,
+                    null,  // intentional
+                ][ (node.start._permute * steps | 0) % 3 ];
+                node.start._permute += step;
+                if (!expr) {
+                    if (node.body[0] instanceof U.AST_Break) {
+                        if (node instanceof U.AST_Do) {
+                            CHANGED = true;
+                            return List.skip;
+                        }
+                        expr = node.condition; // AST_While - fall through
+                    }
+                }
+                if (expr && (expr !== node.body || !has_loopcontrol(expr, node, parent))) {
+                    CHANGED = true;
+                    return to_statement(expr);
+                }
+            }
+            else if (node instanceof U.AST_PropAccess) {
+                var expr = [
+                    node.expression,
+                    node.property instanceof U.AST_Node && node.property,
+                ][ node.start._permute++ % 2 ];
+                if (expr) {
+                    CHANGED = true;
+                    return expr;
+                }
+            }
+            else if (node instanceof U.AST_For) {
+                var expr = [
+                    node.init,
+                    node.condition,
+                    node.step,
+                    node.body,
+                ][ (node.start._permute * steps | 0) % 4 ];
+                node.start._permute += step;
+                if (expr && (expr !== node.body || !has_loopcontrol(expr, node, parent))) {
+                    CHANGED = true;
+                    return to_statement(expr);
+                }
+            }
+            else if (node instanceof U.AST_ForIn) {
+                var expr = [
+                    node.init,
+                    node.object,
+                    node.body,
+                ][ (node.start._permute * steps | 0) % 3 ];
+                node.start._permute += step;
+                if (expr && (expr !== node.body || !has_loopcontrol(expr, node, parent))) {
+                    CHANGED = true;
+                    return to_statement(expr);
+                }
+            }
+            else if (node instanceof U.AST_If) {
+                var expr = [
+                    node.condition,
+                    node.body,
+                    node.alternative,
+                ][ (node.start._permute * steps | 0) % 3 ];
+                node.start._permute += step;
+                if (expr) {
+                    // replace if statement with its condition, then block or else block
+                    CHANGED = true;
+                    return to_statement(expr);
+                }
+            }
+            else if (node instanceof U.AST_Object) {
+                // first property's value
+                var expr = node.properties[0] instanceof U.AST_ObjectKeyVal && node.properties[0].value;
+                if (expr) {
+                    node.start._permute++;
+                    CHANGED = true;
+                    return expr;
+                }
+            }
+            else if (node instanceof U.AST_SimpleStatement) {
+                if (node.body instanceof U.AST_Call && node.body.expression instanceof U.AST_Function) {
+                    // hoist simple statement IIFE function expression body
+                    node.start._permute++;
+                    if (!has_exit(node.body.expression)) {
+                        var body = node.body.expression.body;
+                        node.body.expression.body = [];
+                        CHANGED = true;
+                        return List.splice(body);
+                    }
+                }
+            }
+            else if (node instanceof U.AST_Switch) {
+                var expr = [
+                    node.expression,                         // switch expression
+                    node.body[0] && node.body[0].expression, // first case expression or undefined
+                    node.body[0] && node.body[0],            // first case body or undefined
+                ][ (node.start._permute * steps | 0) % 4 ];
+                node.start._permute += step;
+                if (expr && (!(expr instanceof U.AST_Statement) || !has_loopcontrol(expr, node, parent))) {
+                    CHANGED = true;
+                    return expr instanceof U.AST_SwitchBranch ? new U.AST_BlockStatement({
+                        body: expr.body.slice(),
+                        start: {},
+                    }) : to_statement(expr);
+                }
+            }
+            else if (node instanceof U.AST_Try) {
+                var body = [
+                    node.body,
+                    node.bcatch && node.bcatch.body,
+                    node.bfinally && node.bfinally.body,
+                    null,  // intentional
+                ][ (node.start._permute * steps | 0) % 4 ];
+                node.start._permute += step;
+                if (body) {
+                    // replace try statement with try block, catch block, or finally block
+                    CHANGED = true;
+                    return new U.AST_BlockStatement({
+                        body: body,
+                        start: {},
+                    });
+                } else {
+                    // replace try with a break or return if first in try statement
+                    if (node.body[0] instanceof U.AST_Break
+                        || node.body[0] instanceof U.AST_Return) {
+                        CHANGED = true;
+                        return node.body[0];
+                    }
+                }
+            }
+            else if (node instanceof U.AST_Unary) {
+                node.start._permute++;
+                CHANGED = true;
+                return node.expression;
+            }
+            else if (node instanceof U.AST_Var) {
+                if (node.definitions.length == 1 && node.definitions[0].value) {
+                    // first declaration value
+                    node.start._permute++;
+                    CHANGED = true;
+                    return to_statement(node.definitions[0].value);
+                }
+            }
+            else if (node instanceof U.AST_LabeledStatement) {
+                if (node.body instanceof U.AST_Statement
+                    && !has_loopcontrol(node.body, node.body, node)) {
+                    // replace labelled statement with its non-labelled body
+                    node.start._permute = REPLACEMENTS.length;
+                    CHANGED = true;
+                    return node.body;
+                }
+            }
+
+            if (in_list) {
+                // special case to drop object properties and switch branches
+                if (parent instanceof U.AST_Object
+                    || parent instanceof U.AST_Switch && parent.expression != node) {
+                    node.start._permute++;
+                    CHANGED = true;
+                    return List.skip;
+                }
+
+                // replace or skip statement
+                if (node instanceof U.AST_Statement) {
+                    node.start._permute++;
+                    CHANGED = true;
+                    return List.skip;
+                }
+
+                // remove this node unless its the sole element of a (transient) sequence
+                if (!(parent instanceof U.AST_Sequence) || parent.expressions.length > 1) {
+                    node.start._permute++;
+                    CHANGED = true;
+                    return List.skip;
+                }
+            }
+
+            // replace this node
+            var newNode = U.parse(REPLACEMENTS[node.start._permute % REPLACEMENTS.length | 0], {
+                expression: true,
+            });
+            if (is_statement(node)) {
+                newNode = new U.AST_SimpleStatement({
+                    body: newNode,
+                    start: {},
+                });
+            }
+            newNode.start._permute = ++node.start._permute;
+            CHANGED = true;
+            return newNode;
+        }, function(node, in_list) {
+            if (node instanceof U.AST_Sequence) {
+                // expand single-element sequence
+                if (node.expressions.length == 1) return node.expressions[0];
+            }
+            else if (node instanceof U.AST_Try) {
+                // expand orphaned try block
+                if (!node.bcatch && !node.bfinally) return new U.AST_BlockStatement({
+                    body: node.body,
+                    start: {},
+                });
+            }
+            else if (node instanceof U.AST_Var) {
+                // remove empty var statement
+                if (node.definitions.length == 0) return in_list ? List.skip : new U.AST_EmptyStatement({
+                    start: {},
+                });
+            }
+        });
+
+        for (var pass = 1; pass <= 3; ++pass) {
+            var testcase_ast = U.parse(testcase);
+            testcase_ast.walk(new U.TreeWalker(function(node) {
+                // unshare start props to retain visit data between iterations
+                node.start = JSON.parse(JSON.stringify(node.start));
+                node.start._permute = 0;
+            }));
+            for (var c = 0; c < max_iterations; ++c) {
+                if (verbose) {
+                    if (pass == 1 && c % 25 == 0) {
+                        console.error("// reduce test pass "
+                            + pass + ", iteration " + c + ": " + testcase.length + " bytes");
+                    }
+                }
+                var CHANGED = false;
+                var code_ast = testcase_ast.clone(true).transform(tt);
+                if (!CHANGED) break;
+                try {
+                    var code = code_ast.print_to_string();
+                } catch (ex) {
+                    // AST is not well formed.
+                    // no harm done - just log the error, ignore latest change and continue iterating.
+                    console.error("*** Error generating code from AST.");
+                    console.error(ex);
+                    console.error("*** Discarding permutation and continuing.");
+                    continue;
+                }
+                var diff = producesDifferentResultWhenMinified(result_cache, code, minify_options, max_timeout);
+                if (diff) {
+                    if (diff.timed_out) {
+                        // can't trust the validity of `code_ast` and `code` when timed out.
+                        // no harm done - just ignore latest change and continue iterating.
+                    } else if (diff.error) {
+                        // something went wrong during minify() - could be malformed AST or genuine bug.
+                        // no harm done - just log code & error, ignore latest change and continue iterating.
+                        console.error("*** Error during minification.");
+                        console.error(code);
+                        console.error(diff.error);
+                        console.error("*** Discarding permutation and continuing.");
+                    } else if (is_error(diff.unminified_result)
+                        && is_error(diff.minified_result)
+                        && diff.unminified_result.name == diff.minified_result.name) {
+                        // ignore difference in error messages caused by minification
+                    } else {
+                        // latest permutation is valid, so use it as the basis of new changes
+                        testcase_ast = code_ast;
+                        testcase = code;
+                        differs = diff;
+                    }
+                }
+            }
+            if (c == 0) break;
+            if (verbose) {
+                console.error("// reduce test pass " + pass + ": " + testcase.length + " bytes");
+            }
+        }
+        testcase = U.minify(testcase, {
+            compress: false,
+            mangle: false,
+            output: {
+                beautify: true,
+                braces: true,
+                comments: true,
+            },
+        });
+        testcase.code += [
+            "",
+            "// output: " + to_comment(differs.unminified_result),
+            "// minify: " + to_comment(differs.minified_result),
+            "// options: " + to_comment(minify_options_json),
+        ].join("\n").replace(/\u001b\[\d+m/g, "");
+        return testcase;
+    }
+};
+
+function to_comment(value) {
+    return ("" + value).replace(/\n/g, "\n// ");
+}
+
+function has_exit(fn) {
+    var found = false;
+    var tw = new U.TreeWalker(function(node) {
+        if (found) return found;
+        if (node instanceof U.AST_Exit) {
+            return found = true;
+        }
+        if (node instanceof U.AST_Scope && node !== fn) {
+            return true; // don't descend into nested functions
+        }
+    });
+    fn.walk(tw);
+    return found;
+}
+
+function has_loopcontrol(body, loop, label) {
+    var found = false;
+    var tw = new U.TreeWalker(function(node) {
+        if (found) return true;
+        if (node instanceof U.AST_LoopControl && this.loopcontrol_target(node) === loop) {
+            return found = true;
+        }
+    });
+    if (label instanceof U.AST_LabeledStatement) tw.push(label);
+    tw.push(loop);
+    body.walk(tw);
+    return found;
+}
+
+function is_error(result) {
+    return typeof result == "object" && typeof result.name == "string" && typeof result.message == "string";
+}
+
+function is_timed_out(result) {
+    return is_error(result) && /timed out/.test(result);
+}
+
+function is_statement(node) {
+    return node instanceof U.AST_Statement && !(node instanceof U.AST_Function);
+}
+
+function merge_sequence(array, node) {
+    if (node instanceof U.AST_Sequence) {
+        array.push.apply(array, node.expressions);
+    } else {
+        array.push(node);
+    }
+    return array;
+}
+
+function to_sequence(expressions) {
+    if (expressions.length == 0) return new U.AST_Number({value: 0, start: {}});
+    if (expressions.length == 1) return expressions[0];
+    return new U.AST_Sequence({
+        expressions: expressions.reduce(merge_sequence, []),
+        start: {},
+    });
+}
+
+function to_statement(node) {
+    return is_statement(node) ? node : new U.AST_SimpleStatement({
+        body: node,
+        start: {},
+    });
+}
+
+function run_code(result_cache, code, toplevel, timeout) {
+    var key = crypto.createHash("sha1").update(code).digest("base64");
+    return result_cache[key] || (result_cache[key] = sandbox.run_code(code, toplevel, timeout));
+}
+
+function producesDifferentResultWhenMinified(result_cache, code, minify_options, max_timeout) {
+    var minified = U.minify(code, minify_options);
+    if (minified.error) return minified;
+
+    var toplevel = minify_options.toplevel;
+    var elapsed = Date.now();
+    var unminified_result = run_code(result_cache, code, toplevel, max_timeout);
+    elapsed = Date.now() - elapsed;
+    var timeout = Math.min(100 * elapsed, max_timeout);
+    var minified_result = run_code(result_cache, minified.code, toplevel, timeout);
+
+    if (sandbox.same_stdout(unminified_result, minified_result)) {
+        return is_timed_out(unminified_result) && is_timed_out(minified_result) && {
+            timed_out: true,
+        };
+    }
+    return {
+        unminified_result: unminified_result,
+        minified_result: minified_result,
+        elapsed: elapsed,
+    };
+}
+Error.stackTraceLimit = Infinity;

test/sandbox.js

@@ -54,14 +54,15 @@ function createContext() {
     }
 }
 
-exports.run_code = function(code, toplevel) {
+exports.run_code = function(code, toplevel, timeout) {
+    timeout = timeout || 5000;
     var stdout = "";
     var original_write = process.stdout.write;
     process.stdout.write = function(chunk) {
         stdout += chunk;
     };
     try {
-        vm.runInContext(toplevel ? "(function(){" + code + "})()" : code, createContext(), { timeout: 5000 });
+        vm.runInContext(toplevel ? "(function(){" + code + "})()" : code, createContext(), { timeout: timeout });
         return stdout;
     } catch (ex) {
         return ex;
@@ -76,8 +77,9 @@ function strip_func_ids(text) {
 
 exports.same_stdout = semver.satisfies(process.version, "0.12") ? function(expected, actual) {
     if (typeof expected != typeof actual) return false;
-    if (typeof expected != "string") {
+    if (typeof expected == "object" && typeof expected.name == "string" && typeof expected.message == "string") {
-        if (expected.name != actual.name) return false;
+        if (expected.name !== actual.name) return false;
+        if (typeof actual.message != "string") return false;
         expected = expected.message.slice(expected.message.lastIndexOf("\n") + 1);
         actual = actual.message.slice(actual.message.lastIndexOf("\n") + 1);
     }

test/ufuzz/index.js

@@ -10,6 +10,7 @@ require("../../tools/exit");
 var UglifyJS = require("../..");
 var randomBytes = require("crypto").randomBytes;
 var sandbox = require("../sandbox");
+var reduce_test = require("../reduce");
 
 var MAX_GENERATED_TOPLEVELS_PER_RUN = 1;
 var MAX_GENERATION_RECURSION_DEPTH = 12;
@@ -1051,6 +1052,7 @@ function log_rename(options) {
 }
 
 function log(options) {
+    var options_copy = JSON.parse(options);
     options = JSON.parse(options);
     if (!ok) errorln("\n\n\n\n\n\n!!!!!!!!!!\n\n\n");
     errorln("//=============================================================");
@@ -1069,6 +1071,18 @@ function log(options) {
         errorln(original_result);
         errorln("uglified result:");
         errorln(uglify_result);
+        errorln("//-------------------------------------------------------------");
+        var reduced = reduce_test(original_code, options_copy, {
+            verbose: false,
+        }).code;
+        if (reduced) {
+            errorln();
+            errorln("// reduced test case (output will differ)");
+            errorln();
+            errorln(reduced);
+            errorln();
+            errorln("//-------------------------------------------------------------");
+        }
     } else {
         errorln("// !!! uglify failed !!!");
         errorln(uglify_code);
@@ -1089,6 +1103,20 @@ function log(options) {
     }
 }
 
+function fuzzy_match(original, uglified) {
+    uglified = uglified.split(" ");
+    var i = uglified.length;
+    original = original.split(" ", i);
+    while (--i >= 0) {
+        if (original[i] === uglified[i]) continue;
+        var a = +original[i];
+        var b = +uglified[i];
+        if (Math.abs((b - a) / a) < 1e-10) continue;
+        return false;
+    }
+    return true;
+}
+
 var fallback_options = [ JSON.stringify({
     compress: false,
     mangle: false
@@ -1111,8 +1139,12 @@ for (var round = 1; round <= num_iterations; round++) {
             uglify_code = uglify_code.code;
             uglify_result = sandbox.run_code(uglify_code, o.toplevel);
             ok = sandbox.same_stdout(original_result, uglify_result);
-            if (!ok && o.compress.unsafe_math) {
+            if (!ok && typeof uglify_result == "string" && o.compress.unsafe_math) {
-                ok = sandbox.same_stdout(sandbox.run_code(original_code.replace(/( - 0\.1){3}/g, " - 0.3")), uglify_result, o.toplevel);
+                ok = fuzzy_match(original_result, uglify_result);
+                if (!ok) {
+                    var fuzzy_result = sandbox.run_code(original_code.replace(/( - 0\.1){3}/g, " - 0.3"));
+                    ok = sandbox.same_stdout(fuzzy_result, uglify_result);
+                }
             }
         } else {
             uglify_code = uglify_code.error;

test/ufuzz/job.js

@@ -12,17 +12,16 @@ function spawn(endTime) {
     ], {
         stdio: [ "ignore", "pipe", "pipe" ]
     }).on("exit", respawn);
-    var line = "";
+    var stdout = "";
     child.stdout.on("data", function(data) {
-        line += data;
+        stdout += data;
     });
-    child.stderr.once("data", function() {
+    var stderr = "";
-        process.exitCode = 1;
+    child.stderr.on("data", trap).pipe(process.stdout);
-    }).pipe(process.stdout);
     var keepAlive = setInterval(function() {
-        var end = line.lastIndexOf("\r");
+        var end = stdout.lastIndexOf("\r");
-        console.log(line.slice(line.lastIndexOf("\r", end - 1) + 1, end));
+        console.log(stdout.slice(stdout.lastIndexOf("\r", end - 1) + 1, end));
-        line = line.slice(end + 1);
+        stdout = stdout.slice(end + 1);
     }, ping);
     var timer = setTimeout(function() {
         clearInterval(keepAlive);
@@ -31,9 +30,17 @@ function spawn(endTime) {
     }, endTime - Date.now());
 
     function respawn() {
-        console.log(line);
+        console.log(stdout.replace(/[^\r\n]*\r/g, ""));
         clearInterval(keepAlive);
         clearTimeout(timer);
         spawn(endTime);
     }
+
+    function trap(data) {
+        stderr += data;
+        if (~stderr.indexOf("\nminify(options):\n")) {
+            process.exitCode = 1;
+            child.stderr.removeListener("data", trap);
+        }
+    }
 }

tools/exports.js

@@ -1,4 +1,5 @@
 exports["Dictionary"] = Dictionary;
+exports["List"] = List;
 exports["minify"] = minify;
 exports["parse"] = parse;
 exports["push_uniq"] = push_uniq;